Studying effects of external conditions of electrochemical measurements on the photoelectrochemical properties of semiconductors: cyclic voltammetry, impedance spectroscopy, and Mott – Schottky method

Abstract

In this paper, the dependences of the semiconductors’ photoelectrochemical properties on the experimental conditions were studied for the solid solution of CdS and ZnS, graphitic carbon nitride, and the platinized carbon nitride. The cyclic voltammograms were obtained under different scan rates. The sample investigations were carried out by two ways, at the constant external voltage and varied amplitudes and at different external voltages and the fixed amplitude. The Mott – Schottky dependences were studied at different frequencies. The basic dependences of the changes in the photoelectrode target characteristics on the experimental condition were found. Some recommendations for the correct comparison of qualitative and quantitative photoelectrochemical data were formulated.

Photoelectrochemical properties of Pt- and Ir-modified graphitic carbon nitride

“…This result can be associated with the amount of energy required for electron transfer from the corresponding particle. The work function of metallic co-catalysts and g-C3N4 [43] decreases in the following sequence: Pt > Ir > g-C3N4. Thus, the energy required for electron transfer from the electrode to the electrolyte and the open circuit voltage (energy reserve during the photoelectrochemical process) decrease in the same sequence.…”