Improvements of CdS Film Photoanodic Behavior by Sulfur Organic Reducing Agents

The influence of aromatic sulfur reductants on the photoanodic behavior of CdS films is examined. Thiocresol does not substantially improve the characteristics of the i/V curve, contrary to p‐mercaptobenzoic acid which increases the fill factor during illumination. XPS shows that the disulfide and the cadmium salt of thiocresol are formed on the CdS , blocking the charge transfer across the electrode‐solution interface. On the other hand, the binding of p‐mercaptobenzoic acid to the CdS after irradiation, evidenced by XPS, would be responsible for the enhancement of the photoconversion yield.