FIELD OF THE INVENTION Thepresent invention relates to photocatalytic materials, and, more particularly, to anovel composition of photocatalytic material, process for producingthe novel photocatalytic material, and various articles on which the photocatalytic material are applied. 5 BACKGROUNDOF THE INVENTION Photoreactions refer to chemical reactions induced by light. One type of photoreaction is photocatalysis. In a typical photocatalytic process,light is absorbed by an adsorbed substrateto create electron-hole pairs, which generate free radicals (e.g. hydroxyl radicals: 10 *OH) along with oxygen. These free radicals are able to undergo very useful secondary reactions.For example, the free radicals are able to react with organic contaminants to @ decompose them. Therefore, such a reaction hasan ability to clean air, whereinoffensive, odourus, harmful gases, or the like, are decomposed to harmless forms leading to a reduction in the quantity of these unwanted elements in the surroundings. 15 Various materials have been used for photocatalytic process. One such material is titanium dioxide (Ti02). Usually, Ti02 absorbs Ultraviolet (UV)* radiation from sunlight or illuminated light source (fluorescent lamps), thereby producing electrons and holes. The electron of the valence band of titanium dioxide becomes excited when illuminated by light. The excess energy of this excited electron promotes the electron to the conduction 20 band of titanium dioxide therefore creating the negative-electron (e-) and positive-hole (h+) pair.The photocatalytic oxidation of an organic species often proceeds via adsorption of the pollutant on the surface of the catalyst, followed by direct subtraction of the pollutant's a electrons by positively charged holes. Another possible way is oxidation with OH radicals, generated from water of the aqueous environment, which takes place at the catalyst surface or 25 in its vicinity. Both reactions may proceed simultaneously and which mechanism dominates depends on the chemical and adsorption properties of the pollutant. Therefore, it will be appreciated that there is a reasonable need to improve the photocatalysis process so as to provide means to clean pollutants from ambient air. Various ways are known for improving the utility of the photocatalysis process. For 30 example, the utility of the process could be increased by developing new and better photocatalytic materials, which have betterrates of cleaning the pollutants. Another way of improving the utility of the process is by developing new techniques by which better quality photocatalytic materials can be derived at a cheaper rate. Yet another way includes finding out efficient ways of increasing the practicability of such a process so as to make it easily available commercially. Therefore, there is a continuous need for improving the photocatalysis process for variety of applications. More particularly, there is a need of water soluble photocatalytic materials, making them easily applicable on various articles by conventional process. Further, there is a need of having photocatalytic materials that have high rate of deodizing and purifying its surroundings. Furthermore there is a need of having photocatalytic materials capable of absorbing the ultra violet light from the visible light spectrum, thereby neutralizing the bad effects of ultra violet light. Additionally, there is a need of having photocatalytic materials which are easy to obtain, durable and inexpensive to manufacture. Moreover, there is a need for manufacturing articles by applying photocatalytic materials which can be easily used by mankind and such articles with photocatalytic materials coated on them may act as a good absorbent of ultra violet light from the visible light spectrum, cleaning ambient air without degrading the luminance of light. SUMMARY OF THE INVENTION Disclosed is a process for producing Ti02 based photocatalytic material, the Ti02 based material obtained by the process and various articles with the material being applied thereon. The invention relates to a water soluble photocatalytic material capable of being adhered to an article by a conventional coating process.The photocatalytic material includesa doped metal oxide substrate capable of exhibiting photocatalytic behavior on being exposed to visible light, wherein particle size of doped metal oxide substrate ranges from about 18 nanometer (nm) to about 35 nm. In one embodiment, the doped metal oxide substrate is doped Ti02 substrate. Further, the photocatalytic material includes a polymeric adhesive for improving the adhering property of the doped metal oxide substrate on the article. In one embodiment, the polymeric adhesive is in liquid state and is NORA 485. In another aspect, an air purifying article has been disclosed which includesa base element anda photocatalytic material applied to the base element. The photocatalytic materialhasa doped metal oxide substrate capable of exhibiting photo catalytic behavior on 3 being exposed to visible light, wherein particle size of doped metal oxide substrate ranges from about 18 nanometer (nm) to about 35 nm. In one embodiment, the doped metal oxide substrate is doped Ti02 substrate. Further, the photocatalytic material includes a polymeric adhesive for improving the adhering property of the doped metal substrate on the base element.In one embodiment, the polymeric adhesive is in liquid state and is NORA 485. This together with the other aspects of the present invention along with the various features of novelty that characterized the present disclosure is pointed out with particularity in claims annexed hereto and forms a part of the present invention. For better understanding of the present disclosure, its operating advantages, and the specified object attained by its uses, reference should be made to the accompanying descriptive matter in which there are illustrated exemplary embodiments of the present invention. DESCRIPTION OF THE DRAWINGS The features of the present invention will become better understood with reference to the following detailed description taken in conjunction with the accompanying drawing, in which: Fig. 1 illustrates nano particles of Ti02 with different percentages of Platinum (Pt) doped in it, in accordance with an embodiment of the present invention; Fig. 2 shows the anti-baterial and anti-fungal property of the CFL lamp coated with the photocatalytic material as tested by LIT Kharagpur's testing lab, in accordance with an embodiment of the present invention; and Fig. 3 shows the air cleaning property of the CFL lamp coated with the photocatalytic material installed in a ladies toilet. DESCRIPTION OF THE INVENTION For a thorough understanding of the present disclosure, reference is to be made to the following detailed description, including the appended claims. Although the present disclosure is described in connection with exemplary embodiments, the present invention is not intended to be limited to the specific forms set forth herein. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or 4 render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The terms "a" and "an" herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. The terms "having", "comprising", "including", and variations thereof signify the presence of a component. The present invention relates to photocatalytic materials, and more particularly, to a 10 novel photocatalytic material, process of developing the photocatalytic material, and various articles on which the materials may be applied.lt should be understood to a person skilled in the art that the term photocatalytic material as mentioned herein refers to a composition that has the property of initiating molecular transformation or reactions at its surface. Such photocatalytic materials have various applications, especially in inducing molecular 15 transformation of organic pollutants, thereby neutralizing them. More particularly, the photocatalytic materials oxidize the organic pollutants to neutralize them. The present invention discloses a water soluble photocatalytic material capable of being adhered to an article by a conventional coating process. The water soluble nature of the photocatalytic material makes it easily applicable on various articles by conventional coating 20 process, such as dip coating process.The composition of the photocatalytic material will now be described in details. The photocatalytic material includes an active substrate that is the substrate which is capable of exhibiting photocatalytic behaviour. In one embodiment, the substrate isa doped metal oxide substrate.In one embodiment, the metal oxide is a transition metal oxide 25 substrate. In one embodiment, the metal oxide substrate is Ti02 substrate.1n another embodiment, the metal oxide substrate is Ti02 substrate in anatase phase. It will be appreciated by those skilled in the art that the Ti02 substrate has been known to have a property of initiating photocatalysis. This substrate is capable of exhibiting photocatalytic 30 behaviour on being exposed to visible light, specifically light in ultra violet region.Such exposure produces causes the valence band electrons. 5 More specifically, the titania substrate when illuminated by UV radiation with a wavelength sufficient todisplace electrons from the valence band of the catalyst; for titanium dioxide this is beIow387.5 nm.An electron/hole pair is produced on the semiconductor surface.Thephotocatalytic oxidation of an organic species often proceeds via adsorption of 5 thepollutant on the surface of the catalyst, followed by direct subtraction of the pollutant'selectrons by positively charged holes. In one embodiment, the Ti02 substrate is doped Ti02 substrate. It will be apparent to a person skilled in the art that the doping may be done to improve the photocatalytic activity of the substrate. More specifically, the doping allows the Ti02 substrate to show enhanced 10 activity even under visible light with wavelength greater than 400 nm, i.e., the doping inducing impurity in the band gap of the Ti02 substrate, which leads to absorption in visiblelight. In one embodiment, the doping is done by at least one metallic element. In another embodiment, the doping is done by at least one non-metal. The suitable examples of metal 15 dopants may include transition metal, such as Platinum (Pt), Boron and Cerium (B-Cecodoped), Iron and Zinc, Silver, and the like. However, such examples of the metallic dopants should not be construed as a limitation of the present invention. In one embodiment of the present invention, the Ti02 substrate is doped with Pt, which gives the best photocatalytic activity to the substrate. 20 The suitable examples of the non-metallic dopants may include, but are not limited to, Nitrogen, Carbon, Flourine, Iodine, and the like. In one embodiment of the present invention, the non-metallic dopant is Nitrogen. The doped Ti02 particles of the present invention have a specific size. The size of the doped Ti02 substrate is in the range of 18 nanometer (nm) to about 35 nm. Such size of the 25 nano particles provides a specific character to the photocatalytic material, by increasing the photocatalytic activity of the Ti02 substrate manifold. Such increase of the photocatalytic activity is a direct result of the increased surface area of the Ti02 particles in aforesaid particle range. However, it should be clearly understood that such particle range of the photocatalytic particles should not be construed as a limitation to the present invention. The photocatalytic material of the present invention further includes a polymeric adhesive. The polymeric adhesive is provided for improving the adhering property of the water soluble photocatalytic material on various articles on which the photocatalytic material may be applied. The polymeric adhesive is preferably in liquid state. Suitable examples of the polymeric adhesive includes, but are not limited to, Polyurethanes, Acrylics, Acetates, such as Polyvinyl Acetates, Polychloroprenes, and the like. In one embodiment, the polymeric adhesive isvinyl Acetate. However, it should be understood that such examples of the polymeric adhesives should not be construed as a limitation to the present invention, accordingly, any polymeric adhesive capable of forming a liquid phase with aforesaid metal oxide substrate, and especially, Ti02 substrate, is equally applicable in the present invention. In one embodiment, the polymeric adhesive is NORA@ 485, which is a waterborne acrylic based adhesive supplied by Nora Systems GmbH. This adhesive is also available under the Trade Name and Synonyms as Nora 485 Acrylic Adhesive, and under Chemical Family of Acrylic copolymer dispersion. The adhesive essentially includes60-64 % of Acrylic copolymer, 35-39 % of Calcium carbonate and