Bismuth Vanadate (BiVO4) as Counter Electrode in the Newly Developed Catalysis Zone of Modified Cadmium Sulfide (CdS) Sensitized Solar Cell for Hydrogen Production.

Recently we developed a modified quantum dot dyes sensitized solar cell (QD-DSSC) having catalysis zone extension for hydrogen production. The DSSC section comprised of CdS sensitized highly order Titanium dioxidenanotube (CdS-HOTN) immobilized on Ti plate, Na2S/S containing electrolyte, and Pt covered SnO-F (fluorine doped tin oxide) glass plate (hence Pt/SnO-F/Glass). While the catalysis zone comprised of an extension of Ti support, as cathode, and the respected counter electrode was an extension of SnO-F glass, which was covered by BiVO4 film, both from respected DSSC section. In this presentation, we will focus on the role of the BiVO4 in our newly developed system. The bismuth vanadate was prepared by co-precipitation method with ammonia and calcination to obtain a fine powder. The BiVO4 fine powder were then deposited onto SnO-F glass plate and characterized by FT-IR, UV-vis diffused reflectance spectroscopy, SEM and X-ray diffraction. The characterization results revealed that the BiVO4 film, typically, has a band gap of 2.35 eV, characteristic of IR peaks represent the -V-O-, and -Bi-O-V- bonds, having a crystal phase as BiVO4 monoclinic scheelite with a typically crystallite size of 74.06 nm. The photo-electro-chemical properties of the BiVO4 film photo-anode was investigated by a linear sweep voltammetry and multi pulse amperometry, which revealed that the current response under the visible light was 0.03 mA/cm². Further investigation when the BiVO4 film was incorporated into the modified QD-DSSC, the system (catalysis zone section), under solely visible light, was able to split the water into hydrogen and molecular oxygen. A brief discussion of the newly developed modified QD-DSSC, especially on the role of BiVO4 counter electrode in the catalysis zone will be presented, to gain a better insight in our new type artificial photosynthesis. [ABSTRACT FROM AUTHOR]