Claims:FIELD OF INVENTION
The present disclosure provides a proton exchange membrane for fuel cells. Particularly, the present disclosure relates to a proton exchange membrane having an inorganic-organic hybrid material.

BACKGROUND
Polymer Electrolyte Membrane (PEM) fuel cell is an electrochemical energy conversion device that converts chemical energy into electrical energy and heat as long as the fuel is supplied. The performance of a proton exchange membrane is key to the performance of a PEM fuel cell. Hence, efficiency of PEM fuel cells can be improved by using an excellent proton exchange membrane. The major factors to be considered for any membrane to be used in fuel cells are mechanical, chemical and thermal stability thereof.
Nafion is a widely-used proton exchange membrane in the fuel cells. However, Nafion like compounds have poor proton conductivity at low humidity, which limits the efficiency of PEM fuel cells. Hence, there is need to develop an efficient proton exchange membrane. Towards achieving this objective, a number of proton exchange membranes have been developed.
US patent application number 10/450,845 discloses a cross linkable proton conducting membrane, having a cross linked structure by a silicon-oxygen bond. A process to produce same is also disclosed. The proton conducting membrane comprises an organic/inorganic hybrid structure which is covalently bonded to at least two silicon-oxygen crosslinks, having a carbon atom. Further the proton exchange membrane also comprises an acid structure, having an acid group which is covalently bonded to silicon-oxygen crosslinks. However, the membrane shows poor performance in fuel cell application i.e., less than 120 mA/cm2 at 0.6 V and high proton conductivity is not achieved at high humidity. Also, the process disclosed does not achieve uniform pore size of the organic/inorganic hybrid structure. Furthermore, the process disclosed is energy intensive and not cost effective as the experiments are performed at a very high temperature.
US application number 2004/0101760 discloses organic-inorganic hybrid polymer blends and hybrid blend membranes. The disclosed membrane contains at least one polymeric acid halide, characterized in that before, during or after the membrane formation process salts, metal oxides or metal hydroxides or their organic precursors are incorporated into the membrane. Further, lower concentration of acid sites i.e., 0.77–0.81 mmol/g leads to lower proton conductivity and ultimately swelling is very high. The disclosed hydrothermal synthesis process is energy intensive and hence not suitable for PEM fuel cell applications.
US application number 2011/0217623 relates to a proton exchange membrane for fuel cells operating at elevated temperatures. The document discloses an inorganic proton conducting electrolyte consisting of a mesoporous crystalline metal oxide matrix and a heteropolyacid bound within the mesoporous matrix. Further, as per the disclosed process heteropolyacid is blended with mesoporous silica as a physical mixture. In such a case, there is a possibility of heteropolyacid leaching out during reaction. Leaching of heteropolyacid during the reaction, leads to decrease in power density in due course of time. Hence, power density thus obtained is poor i.e., 180 mW/cm2.
The membranes disclosed above are neither stable nor flexible, hence cannot be efficiently used in fuel cell applications.

SUMMARY
A proton exchange membrane for a proton exchange membrane fuel cell is disclosed. Said proton exchange membrane comprises an inorganic-organic hybrid material having a general formula R–SiO1.5–M1–O–SiO2–O–M2–O1.5Si–R.
A process for synthesis of said proton exchange membrane comprising an inorganic-organic hybrid material is also disclosed.

BRIEF DESCRIPTION OF DRAWINGS
Figure 1 illustrates a schematic representation of hydrothermal synthesis of inorganic-organic hybrid materials in accordance with an embodiment of the present disclosure.
Figure 2 illustrates XRD patterns of (a) hexagonal structure, and (b) wormhole structure of mesoporous inorganic-organic hybrid material in accordance with the present disclosure.

DETAILED DESCRIPTION
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the disclosed process and system, and such further applications of the principles of the invention therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.
Reference throughout this specification to “one embodiment” “an embodiment” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in one embodiment”, “in an embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
The present disclosure relates to a proton exchange membrane for fuel cells. Particularly, the present disclosure relates to proton exchange membrane comprising an inorganic-organic hybrid material, for application in PEM fuel cells. The disclosure also relates to a process for synthesis of said proton exchange membrane comprising an inorganic-organic hybrid material.
Said proton exchange membrane for a fuel cell comprises an inorganic-organic hybrid material having a general formula (I):
R–SiO1.5–M1–O–SiO2–O–M2–O1.5Si–R (I)
Where:
R = –(CH2)x–SO3H and –(CH2)x–SH;
x = 3 to 12;
M1 is a first metal selected from Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu; and
M2 is a second metal selected from Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu.
In accordance with an embodiment, the inorganic-organic hybrid material has a general formula (II):
(II)
Where:
M1 is a first metal selected from a group consisting of Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu;
M2 is a second metal selected from a group consisting of Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu; and
y = 1 to 10.
In accordance with a specific embodiment, the sulfonic acid group is attached to the inorganic-organic hybrid material through a propyl linkage.
In accordance with an embodiment, M1 is a first metal selected from the group consisting of titanium, zirconium, iron, stannum, molybdenum, vanadium, niobium, tantalum, tungsten, cobalt, nickel and copper, and is preferably titanium. In accordance with an embodiment, titanium and other oxides present in the inorganic-organic hybrid material enables dissociation of water in the presence of sunlight.
In accordance with an embodiment, M2 is a second metal selected from the group consisting of titanium, zirconium, iron, stannum, molybdenum, vanadium, niobium, tantalum, cobalt, nickel and copper, and is preferably titanium, zirconium, niobium, tantalum and stannum.
In accordance with an embodiment, M1 and M2 may be same or different metals.
In accordance with an embodiment, the combination of M1 and M2 in inorganic-organic hybrid material is selected from a group consisting of Ti-Zr, Ti-Mo, Ti-W, Ti-V, Ti-Fe, Ti-Sn, Ti-Nb, Ti-Ta, Ti-Co, Ti-Ni, Ti-Cu, Zr-Mo, Zr-W, Zr-V, Zr-Fe, Zr-Sn, Zr-Nb, Zr-Ta, Zr-Co, Zr-Ni, Zr-Cu, Mo-W, Mo-V, Mo-Fe, Mo-Sn, Mo-Nb, Mo-Ta, Mo-Co, Mo-Ni, Mo-Cu, W-V, W-Fe, W-Sn, W-Nb, W-Ta, W-Co, W-Ni, W-Cu, V-Fe, V-Sn, V-Nb, V-Ta, V-Co, V-Ni, V-Cu, Fe-Sn, Fe-Nb, Fe-Ta, Fe-Co, Fe-Ni and Fe-Cu. Preferably, combination of oxides of Ti-Zr, Ti-Sn, Ti-Nb and Ti-Ta are used.
In accordance with an embodiment, the molar ratio of M1 to M2 in the inorganic-organic hybrid material is in the range of 1:1 and 1:3. In accordance with a specific embodiment, the molar ratio of M1 to M2 in the inorganic-organic hybrid material is 1:1.5.
In accordance with an embodiment, the molar ratio of Si: (Si + M1 + M2) in the inorganic-organic hybrid material ranges from 0.50 to 0.98. In accordance with a preferred embodiment, the molar ratio of Si: (Si + M1 + M2) in the inorganic-organic hybrid material is 0.8 to 0.9.
In accordance with an embodiment, R as stated in formula I, is an alkyl sulfonate –(CH2)x–SH) and preferably (3-mercaptopropyl) trimethoxy silane. The thiol group (SH) which is present in the (3-mercaptopropyl) trimethoxy silane is converted into sulfonic acid group by oxidation. Herein the sulfonic acid group acts as a proton conductor. In accordance with an embodiment, the inorganic-organic hybrid material contains a maximum of 6.30 mmol of sulfonic acid groups per gram of the inorganic-organic hybrid material. Herein the higher concentration of sulfonic acid group increases the proton conductivity of the proton exchange membrane.
In accordance with an embodiment, the pore size of the inorganic-organic hybrid material ranges from 0.5 to 8 nm. In a preferred embodiment, the pore size of the inorganic-organic hybrid material is 1 to 3 nm.
In accordance with an embodiment, the proton exchange membrane further comprises a thermoplastic fluoropolymer. Said thermoplastic fluoropolymer is selected from a group consisting of Polyvinylidene fluoride (PVDF), Polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) or Polytetrafluoroethylene (PTFE), and is preferably PVDF-HFP. In accordance with a related embodiment, the proton exchange membrane comprises thermoplastic fluoropolymer in an amount ranging between 30 and 70%.
In accordance with an embodiment, proton exchange membrane may further comprise a fibrous material. In accordance with an embodiment, the fibrous material is selected from a group consisting of short fiber only, long fiber only and a combination thereof.
In accordance with an embodiment, IR opacifiers and/or reinforcement materials are incorporated with the inorganic-organic hybrid material in the proton exchange membrane. In accordance with an embodiment, IR opacifiers and reinforcement materials include but are not limited to carbon black, carbon fiber, boron fiber, ceramic fiber, rayon fiber, nylon fiber, zirconia fiber, alumina clay, titanium dioxide, zinc oxide and combination thereof.
In accordance with an embodiment, the inorganic-organic hybrid material is present in the proton exchange membrane in an amount ranging from 5 to 80%. In accordance with a preferred embodiment, the inorganic-organic hybrid material is present in the proton exchange membrane in an amount of 60%.
In accordance with an embodiment, the inorganic-organic hybrid material has an average of one proton delivering sites per 200 units of atomic weight. Herein the high proton conductivity of the proton exchange membrane is achieved by higher concentration of the proton conducting sulfonic groups per unit atomic weight of the inorganic-organic hybrid material.
In accordance with an embodiment, the proton exchange membrane has a proton conductivity in the range of 0.1 S/cm. In accordance with an embodiment, the proton exchange membrane thickness varies in the range of 5 to 200 µm. In a preferred embodiment, the proton exchange membrane is 30 µm thick.
The present disclosure also relates to a process for synthesis of an inorganic-organic hybrid material for proton exchange membrane fuel cells.
In accordance with an embodiment, a process of synthesizing the inorganic-organic hybrid material of the present invention is disclosed. The process comprises the steps of:
(a) forming an aqueous solution of a mixture of an aliphatic amine and alcohol;
(b) adding a silica precursor and an alkoxysilane to the aqueous solution formed in step (a);
(c) adding a mixture of a first metal alkoxide M1OR, a second metal alkoxide M2OR and 2-propanol to the aqueous solution formed in step (b) and stirring the mixture to synthesize inorganic-organic hybrid material having formula RSiO2-M1-M2-O2SiR;
(d) adding a mixture of HCl and alcohol to the synthesized inorganic-organic hybrid material of step (c) and refluxing the synthesized inorganic-organic hybrid material to obtain a proton exchanged inorganic-organic hybrid material;
(e) adding hydrogen peroxide to the proton exchanged inorganic-organic hybrid material obtained in step (d); and
(f) filtering and drying the proton exchanged inorganic-organic hybrid material obtained in step (e) to form inorganic-organic hybrid material functionalized with -SO3H.
In accordance with an embodiment, the aliphatic amine is selected form a group consisting of 2-propanamine, (S)-1-phenylethanamine, 1-octadecylamine (ODA) and 1,6-hexanediamine. In a specific embodiment, the aliphatic amine is 1-octadecylamine.
In accordance with an embodiment, the silica precursor is selected from a group consisting of tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate (TMOS) and tetrabutoxy (TBOS) and is preferably TEOS.
In accordance with an embodiment, the alkoxysilane is selected form a group consisting of polydimethyloxysiloxane, methyltrimethoxysilane, alkytrialkoxysilane, and tetraethoxysilane. In a specific embodiment, the alkoxysilane is (3-mercarptopropyl) trimethoxysilane (MPTMS).
In accordance with an embodiment, R is an alkyl sulfonate –(CH2)x–SH and is preferably MPTMS.
In accordance with an embodiment, the process is carried out at a temperature of 65°C.
In accordance with an embodiment, ammonia is added to the mixture after step (c) to maintain a pH of 12.
In accordance with an embodiment, the mixture formed after steps (c) and (d) is filtered and dried under vacuum.
In accordance with a specific embodiment, the molar composition of the synthesis on anhydrous basis varies in the range of (0.40–0.70)SiO2 : (0.05–0.40)M1 : (0.00–0.20)M2: (0.10–0.50)MPTMS : (0.10–0.50)ODA : (3–20)EtOH : (100–200)H2O.
Below illustrated examples disclose the synthesis of inorganic-organic hybrid materials.
EXAMPLES
The following examples are provided to explain and illustrate the synthesis of inorganic-organic hybrid material and do not in any way limit the scope of the invention as described and claimed.
The ingredients for the synthesis of inorganic-organic hybrid materials are as follows:
(i) Tetraethyl orthosilicate (TEOS)
(ii) Titanium(IV) butoxide (TiOBu)
(iii) Zirconium n-propoxide (ZrOPr)
(iv) Ferrous sulphate (FeSO4)
(v) Stannous chloride (SnCl2)
(vi) Ammonium heptamolybdate tetrahydrate [(NH4)6Mo7O24]
(vii) Vanadium(V) oxytriisopropoxide (VOPr)
(viii) Niobium(V) ethoxide (NbOEt)
(ix) Tantalum(V) ethoxide (TaOEt)
(x) Tungsten(VI) ethoxide (WOEt)
(xi) Cobalt chloride (CoCl2)
(xii) Nickel sulfate (NiSO4)
(xiii) Copper nitrate (CuNO3)
(xiv) (3-mercaptopropyl) trimethoxy silane (MPTMS)
(xv) 1-Octylamine (OA)
(xvi) 1-dodecylamine (DDA)
(xvii) 1-hexadecylamine (HDA)
(xviii) 1-Octadecylamine (ODA)
(xix) Ethanol (EtOH)
(xx) 2-propanol (IPA)
(xxi) Hydrogen peroxide (H2O2)
(xxii) Deionized water
Example 1
The molar ratio of the ingredients in the synthesis is as follows:
0.40SiO2 : 0.25TiO2 : 0.35MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 33.33 g of TEOS and 27.49 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 34.03 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 48.52 g.
The experiment was repeated with different molar ratio of SiO2:TiO2 in the initial mixture, viz. 0.45:0.20, 0.50:0.15 and 0.60:0.05, by taking 37.50, 41.67 and 50.00 g of TEOS, respectively, and 27.23, 20.42 and 6.81 g of TiOBu, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.56 g
Step 3: Oxidation
In a 100-mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.92 g
Example 2
The molar ratio of the ingredients in the synthesis is as follows:
0.55SiO2 : 0.05TiO2 : 0.40MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 45.83 g of TEOS and 31.41 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.81 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 48.18 g.
The experiment was repeated with different molar ratio of TiO2 : MPTMS in the initial mixture, viz. 0.10:0.35, 0.15:0.30 and 0.20:0.25, by taking 13.65, 20.54 and 27.47 g of TiOBu, respectively, and 27.49, 23.56 and 19.63 g of MPTMS, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.98 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.85 g
Example 3
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.40TiO2 : 0.10MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 7.85 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 55.09 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 40.97 g.
The experiment was repeated with different molar ratio of TiO2 : MPTMS in the initial mixture, viz. 0.30:0.20, 0.20:0.30 and 0.10:0.40, by taking 41.32, 27.55 and 13.77 g of TiOBu, respectively, and 15.71, 23.56 and 31.41 g of MPTMS, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.71 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.88 g
Example 4
The molar ratio of the ingredients in the synthesis is as follows:
0.70SiO2 : 0.10TiO2 : 0.20MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 58.33g of TEOS and 15.71 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 13.61 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 41.37 g.
The experiment was repeated with different molar ratio of SiO2 : MPTMS in the initial mixture, viz. 0.65:0.25, 0.60:0.30 and 0.45:0.45, by taking 54.17, 50.00 and 37.50 g of TEOS, respectively, and 19.73, 23.80 and 36.24 g of MPTMS, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 15.28 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.81 g
Example 5
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.05TiO2 : 0.45MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 35.34 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.81 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 50.02 g.
The experiment was repeated with different molar ratio of ODA in the initial mixture, viz. 0.10, 0.30, 0.40 and 0.50, by taking 10.78, 32.34, 43.12 and 53.90 g of ODA, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.62 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.86 g
Example 6
The molar ratio of the ingredients in the synthesis is as follows:
0.60SiO2 : 0.05TiO2 : 0.35MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 50.00 g of TEOS and 27.49 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.81 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 46.34 g.
The experiment was repeated with other surfactants having different alkyl chain length, viz, hexadecylamine (HDA), dodecylamine (DDA) and octylamine (OA), in place of ODA. The amounts of HDA, DDA and OA used in the syntheses were 21.25, 16.31 and 11.37 g, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.42 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.95 g
Example 7
The molar ratio of the ingredients in the synthesis is as follows:
0.60SiO2 : 0.10TiO2 : 0.30MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 50.00 g of TEOS and 23.56 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 13.61 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 45.05 g.
The experiment was repeated with different molar ratio of deionized water in the initial mixture, viz. 100, 125, 150, 175 and 200, by taking 720, 900, 1080, 1260 and 1440 g of H2O, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.42 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.88 g
Example 8
The molar ratio of the ingredients in the synthesis is as follows:
0.60SiO2 : 0.15TiO2 : 0.25MPTMS : 0.22ODA : 3EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 55 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 50.00 g of TEOS and 19.63 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 20.42 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 43.46 g.
The experiment was repeated with different molar ratio of ethanol in the initial mixture, viz. 8, 12, 15 and 20, by taking 147, 220, 276 and 368 g of EtOH, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.42 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.88 g
Example 9
The molar ratio of the ingredients in the synthesis is as follows:
0.55SiO2 : 0.05TiO2 : 0.40MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 45.83 g of TEOS and 31.41 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.81 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 48.18 g.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.72 g
Step 3: Oxidation
In a 200 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.91 g
The experiment was repeated by varying the amount of H2O2 used in the oxidation, viz. 8, 20, 32, 64 and 80 mL. All other parameters in the oxidation step remain the same.
Example 10
The molar ratio of the ingredients in the synthesis is as follows:
0.55SiO2 : 0.05TiO2 : 0.40MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 45.83 g of TEOS and 31.41 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.81 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 48.18 g.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 15.12 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.90 g
The experiment was repeated by varying the reaction time for H2O2 treatment, viz. 1, 2, 6, 12, 24 and 48 h. All other parameters in the oxidation step remain the same.
Example 11
The molar ratio of the ingredients in the synthesis is as follows:
0.55SiO2 : 0.05TiO2 : 0.40MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 45.83 g of TEOS and 31.41 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.81 g of TiOBu and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 48.18 g.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 15.15 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.89 g
The experiment was repeated by varying the amount of sample in the oxidation step, viz. 0.1, 0.2, 0.5, 1, 2, 6 and 8 g. All other parameters in the oxidation step remain the same.
Example 12
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.05ZrO2 : 0.40MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 31.41 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.55 g of ZrOPr and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 49.37 g.
The experiment was repeated by replacing ZrOPr with different metal precursors in the initial mixture, viz. FeSO4, SnCl2, (NH4)6Mo7O24, VOPr, NbOEt, TaOEt, WOEt, CoCl2, NiSO4 and CuNO3 by taking 3.04, 4.51, 24.72, 4.88, 6.36, 8.13, 9.08, 2.60, 5.26 and 4.83g of the precursors, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.56 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.92 g
Example 13
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.05TiO2 : 0.05ZrO2 : 0.40MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 31.41 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.81 g of TiOBu, 6.55 g of ZrOPr and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 49.92 g.
The experiment was repeated by replacing ZrOPr with different metal precursors in the initial mixture, viz. (NH4)6Mo7O24, WOEt, VOPr, FeSO4, SnCl2, NbOEt, TaOEt, CoCl2, NiSO4 and CuNO3, and by taking 24.72, 9.08, 4.88, 3.04, 4.51, 6.36, 8.13, 2.60, 5.26 and 4.83 g of the precursors, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.45 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.87 g
Example 14
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.05ZrO2 : 0.10MoO3 : 0.35MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 27.49 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.55 g of ZrOPr, 49.44 g of (NH4)6Mo7O24 and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 52.14 g.
The experiment was repeated by replacing ZrOPr with different metal precursors in the initial mixture, viz. WOEt, VOPr, FeSO4, SnCl2, NbOEt, TaOEt, CoCl2, NiSO4 and CuNO3, and by taking 18.17, 9.77, 6.08, 9.03, 12.73, 16.25, 8.13, 5.19, 10.51 and 9.66 g of the precursors, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.76 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.82 g
Example 15
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.10MoO3 : 0.15WO3 : 0.25MPTMS : 0.22ODA : 5EtOH : 161H2O

Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 19.63 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 49.44 g of (NH4)6Mo7O24, 27.25 g of WOEt and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 60.87 g.
The experiment was repeated by replacing WOEt with different metal precursors in the initial mixture, viz. VOPr, FeSO4, SnCl2, NbOEt, TaOEt, CoCl2, NiSO4 and CuNO3, and by taking 14.65, 9.11, 13.54, 19.09, 24.38, 7.79, 15.77 and 14.50 g of the precursors, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.94 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.86 g

Example 16
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.10WO3 : 0.20VO2 : 0.20MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 15.71 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 18.17 g of WOEt, 19.54 g of VOPr and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 52.23 g.
The experiment was repeated by replacing VOPr with different metal precursors in the initial mixture, viz. FeSO4, SnCl2, NbOEt, TaOEt, CoCl2, NiSO4 and CuNO3, and by taking 12.15, 18.06, 25.46, 32.50, 10.39, 21.03 and 19.33 g of the precursors, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.72 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.81 g
Example 17
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.05VO2 : 0.15FeO : 0.30MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 23.56 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 4.88 g of VOPr, 9.11 g of FeSO4 and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 45.56 g.
The experiment was repeated by replacing FeSO4 with different metal precursors in the initial mixture, viz. SnCl2, NbOEt, TaOEt, CoCl2, NiSO4 and CuNO3, and by taking 13.54, 19.09, 24.38, 7.79, 15.77 and 14.50 g of the precursors, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.78 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.75 g
Example 18
The molar ratio of the ingredients in the synthesis is as follows:
0.50SiO2 : 0.10FeO : 0.05SnO : 0.35MPTMS : 0.22ODA : 5EtOH : 161H2O
Step 1
In a 2000 mL beaker, 23.72 g of ODA and 92 g of EtOH were taken and the beaker was kept in hot water until the ODA was completely dissolved in EtOH. Then 1159 g of preheated water was added to the solution and stirred for 30 min keeping the temperature at 65 °C. Then 41.67 g of TEOS and 27.49 g of MPTMS were added and the mixture was stirred for 30 min keeping the temperature at 65 °C. Then 6.08 g of FeSO4, 4.51 g of SnCl2 and 15 g of IPA were added and stirring was continued for 60 min keeping the temperature at 65 °C.
Initial pH of the reaction mixture was 8-9. The final pH was adjusted to 12 by adding ammonia and stirring was continued for 30 min. Then it was filtered and dried under vacuum.
Yield of the solid product = 48.94 g.
The experiment was repeated by replacing SnCl2 with different metal precursors in the initial mixture, viz. NbOEt, TaOEt, CoCl2, NiSO4 and CuNO3, and by taking 6.36, 8.13, 2.60, 5.26 and
4.83 g of the precursors, respectively. All other parameters in the experiment remain the same.
Step 2: Proton-exchange
In a 2000 mL beaker, 20 mL of 2M HCl and 1000 mL of EtOH were added to 20 g of the material and refluxed overnight. Then it was filtered and dried in vacuum connected microwave oven.
Yield of the solid product = 14.66 g
Step 3: Oxidation
In a 100 mL beaker, 40 mL of H2O2 was added to 4 g of the above material and was stirred for 4 h. It was filtered and dried in vacuum oven. The color of the final product is white.
Yield = 3.72 g
The various samples of mesoporous hybrid oxide have been analyzed for chemical composition and proton conductivity.
Table 1. Chemical analysis of the mesoporous inorganic-organic hybrid material samples
Example No. Composition C
(wt%) S
(wt%) Si
(wt%) M1
(wt%) M2
(wt%)
1 (SiO2)0.40 (TiO2)0.25 (O1.5Si-(CH2)3-SO3H)0.35 12.46 9.23 17.31 9.87 -
2 (SiO2)0.55 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 14.35 10.63 22.08 1.99 -
3 (SiO2)0.50 (TiO2)0.40 (O1.5Si-(CH2)3-SO3H)0.10 4.22 3.12 16.40 18.70 -
4 (SiO2)0.70 (TiO2)0.10 (O1.5Si-(CH2)3-SO3H)0.20 8.35 6.19 24.36 4.63 -
5 (SiO2)0.50 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.45 15.55 11.52 21.27 1.91 -
6 (SiO2)0.60 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.35 13.05 9.67 22.96 2.07 -
7 (SiO2)0.60 (TiO2)0.10 (O1.5Si-(CH2)3-SO3H)0.30 11.51 8.52 22.38 4.25 -
8 (SiO2)0.60 (TiO2)0.15 (O1.5Si-(CH2)3-SO3H)0.25 9.87 7.31 21.76 6.56 -
9 (SiO2)0.55 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 14.35 10.63 22.08 1.99 -
12 (SiO2)0.55 (ZrO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 14.00 10.37 21.55 3.70 -
13 (SiO2)0.50 (TiO2)0.05 (ZrO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 13.85 10.26 20.19 1.92 3.65
14 (SiO2)0.50 (ZrO2)0.05 (MoO3)0.10 (O1.5Si-(CH2)3-SO3H)0.35 11.60 8.59 18.26 3.50 7.36
15 (SiO2)0.50 (MoO3)0.10 (WO3)0.15 (O1.5Si-(CH2)3-SO3H)0.25 7.10 5.26 13.80 6.31 18.12
16 (SiO2)0.50 (WO3)0.10 (VO2)0.20 (O1.5Si-(CH2)3-SO3H)0.20 6.62 4.90 15.01 14.08 7.80
17 (SiO2)0.50 (VO2)0.05 (FeO)0.15 (O1.5Si-(CH2)3-SO3H)0.30 11.38 8.43 19.66 2.24 7.35
18 (SiO2)0.50 (FeO)0.10 (SnO2)0.05 (O1.5Si-(CH2)3-SO3H)0.35 12.36 9.15 19.45 4.57 4.85

Table 2: Proton conductivity of the mesoporous inorganic-organic hybrid material samples
Example No. Composition [–SO3H ]
(mmol/g) s
(S/cm)
1 (SiO2)0.40 (TiO2)0.25 (O1.5Si-(CH2)3-SO3H)0.35 5.05 6.00 × 10–2
2 (SiO2)0.55 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 5.81 6.91 × 10–2
3 (SiO2)0.50 (TiO2)0.40 (O1.5Si-(CH2)3-SO3H)0.10 1.71 2.03 × 10–2
4 (SiO2)0.70 (TiO2)0.10 (O1.5Si-(CH2)3-SO3H)0.20 3.38 4.02 × 10–2
5 (SiO2)0.50 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.45 6.30 7.49 × 10–2
6 (SiO2)0.60 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.35 5.29 6.28 × 10–2
7 (SiO2)0.60 (TiO2)0.10 (O1.5Si-(CH2)3-SO3H)0.30 4.66 5.54 × 10–2
8 (SiO2)0.60 (TiO2)0.15 (O1.5Si-(CH2)3-SO3H)0.25 4.00 4.75 × 10–2
9 (SiO2)0.55 (TiO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 5.81 6.91 × 10–2
10 (SiO2)0.55 (ZrO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 5.67 6.74 × 10–2
11 (SiO2)0.50 (TiO2)0.05 (ZrO2)0.05 (O1.5Si-(CH2)3-SO3H)0.40 5.61 6.67 × 10–2
12 (SiO2)0.50 (ZrO2)0.05 (MoO3)0.10 (O1.5Si-(CH2)3-SO3H)0.35 4.70 5.59 × 10–2
13 (SiO2)0.50 (MoO3)0.10 (WO3)0.15 (O1.5Si-(CH2)3-SO3H)0.25 2.87 3.42 × 10–2
14 (SiO2)0.50 (WO3)0.10 (VO2)0.20 (O1.5Si-(CH2)3-SO3H)0.20 2.68 3.19 × 10–2
15 (SiO2)0.50 (VO2)0.05 (FeO)0.15 (O1.5Si-(CH2)3-SO3H)0.30 4.61 5.48 × 10–2
16 (SiO2)0.50 (FeO)0.10 (SnO2)0.05 (O1.5Si-(CH2)3-SO3H)0.35 5.01 5.95 × 10–2

INDUSTRIAL APPLICABILITY
The above disclosed inorganic-organic hybrid material can be used in proton exchange membrane for application in PEM fuel cells. The proton exchange membrane disclosed in the present invention is cost effective and provides good proton conductivity at low humidity, good thermal, mechanical and chemical stability, resistance to aqueous and non-aqueous solutions and limited swelling of the membrane. , Description:We Claim:

1. A proton exchange membrane for a proton exchange membrane fuel cell, the proton exchange membrane comprising an inorganic-organic hybrid material having a general formula:
R–SiO1.5–M1–O–SiO2–O–M2–O1.5Si–R,
where
R = –(CH2)x–SO3H and–(CH2)x–SH;
x = 3–12;
M1 is a first metal selected from Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu; and
M2 is a second metal selected from Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu.

2. The proton exchange membrane as claimed in claim 1, wherein R is an alkyl-sulfonate group and the inorganic-organic hybrid material has a general formula:

where
M1 is a first metal selected from Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu;
M2 is a second metal selected from Ti, Zr, Fe, Sn, Mo, V, Nb, Ta, W, Co, Ni and Cu; and
y = 1 to 10.

3. The proton exchange membrane as claimed in claim 1, wherein Si: (Si +M1+M2) in the inorganic-organic hybrid material has a molar ratio ranging from 0.50 to 0.98.

4. The proton exchange membrane as claimed in claim 1, wherein M1 and M2 are present in the inorganic-organic hybrid material in a molar ratio ranging between 1:1 and 1:3.
5. The proton exchange membrane as claimed in claim 1, wherein a maximum of 6.30 mmol of –SO3H groups are present per gram of the inorganic-organic hybrid material.

6. The proton exchange membrane as claimed in claim 1, wherein M1 is selected from a group consisting of titanium, zirconium and tin.

7. The proton exchange membrane as claimed in claim 1, wherein the pore size of the inorganic-organic hybrid material ranges from 0.5 to 8 nm.

8. The proton exchange membrane as claimed in claim 1, wherein the inorganic-organic hybrid material is present in an amount ranging from 5 to 80%.

9. The proton exchange membrane as claimed in claim 1, further comprising of a thermoplastic fluoropolymer.

10. The proton exchange membrane as claimed in claim 1, having a proton conductivity in the range of 0.1 S/cm.

Dated this 31st day of March, 2017

Sneha Agarwal
Of Obhan & Associates
Agent for the Applicant
Patent Agent No. 1969