1. An electrode, comprising an orthorhombic polymorph of FeIIISO4OH as an electrode
material.
2. The electrode of claim 1, wherein the electrode is a cathode.
5 3. The electrode of claim 1 or 2, wherein the electrode provides a voltage of about 3.2-3.3 V.
4. The electrode of any one of claims 1-3, wherein the electrode shows capacity values of about
95- 105 mAh/g.
5. An electrochemical device, comprising the electrode as claimed in any one of claims 1-4.
6. The electrochemical device as claimed in claim 5, wherein the electrochemical device is a
10 battery.
7. The electrochemical of claim 6, wherein the battery is a Li-ion or a Na-ion battery.
8. The electrode as claimed in any one of claims 1-4, wherein the orthorhombic polymorph of
FeIIISO4OH is synthesized by a method comprising: heating an aqueous solution of ferric
sulphate to a temperature of about 185-195°C for about 4.5-6 hours to obtain the orthorhombic
polymorph of FeIII 15 SO4OH.
9. The electrode as claimed in claim 8, wherein the method comprises cooling the orthorhombic
polymorph of FeIIISO4OH to room temperature to obtain a cooled product; washing the cooled
product with water followed by centrifugation to obtain a residue; washing the residue with an
organic solvent followed by drying the residue at about 65-75°C for about 12 hours to obtain a
dry form of orthorhombic polymorph of FeIII 20 SO4OH.