Electrosynthesis of Bi2O3 thin films and their use in electrochemical supercapacitors

Bismuth oxide (Bi2O3) thin films are grown on copper substrates at room temperature by electrodeposition from an aqueous alkaline nitrate bath. The usefulness of electrochemically deposited Bi2O3 for electrochemical supercapacitors is proposed for the first time. The supercapacitor properties of Bi2O3 electrode are studied in aqueous NaOH solution. The Bi2O3 electrode exhibits very good electrochemical supercapacitive characteristics as well as stability in aqueous NaOH electrolyte. The effect of electrolyte concentration, scan rate, and number of cycles on the specific capacitance of Bi2O3 electrodes has been studied. The highest specific capacitance achieved with the electrodeposited Bi2O3 films is 98 F g−1.