ELECTROCHEMICAL DEPOSITION OF BISMUTH SULFIDE THIN FILMS

Abstract

An urgent task is the development of methods for the synthesis of compounds of metals and semiconductors with mixed anions (for example, chalcohalides or sulfur halides) with an advanced morphology, capable of absorbing a wide range of solar radiation. An important task is the fabrication of photoelectrodes for the implementation of photoelectrochemical, photocatalytic reactions in liquid media (PEC cells). This paper describes the effect of the electrolyte solution, the concentration of the initial reagents and the substrate material on the electrochemical behavior of bismuth and sulfur ions. Cyclic voltammetry, XRD, SEM, photoelectrochemical measurements were used for characterization. The optimal conditions for the electrochemical synthesis of bismuth sulfide thin films are determined. The surface morphology and composition of Bi2S3 were dependent on the synthesis potentials. Bi2S3 thin films, obtained at E= -750 mV, possessed a continuous surface and high crystallinity, and demonstrate the photocurrent density 22 μA/cm2 in 0.5 M Na2SO4 under AM1.5G illumination. The achieved photoelectrochemical characteristics prove the applicability of the synthesized bismuth sulfide thin films in photoelectrochemical devices.