Constructing High Efficient Carrier Channels in Double Ternary Compounds Mosse/Cdsse Heterojunction for Photoelectrochemical and Electrocatalytic Hydrogen Production

Abstract

Here is a demonstration of constructing MoSSe/CdSSe heterojunction catalyst from bimetallic selenium sulfides. CdSSe has a high conduction band position of -0.65 eV, resulting in a strong reduction potential of photogenerated electrons. However, the high resistance of CdSSe affects the transport of charge carriers. In addition, experiments have confirmed that the presence of S and Se in MoSSe and CdSSe enhances their chemical activity and facilitates bonding. A better connection can be formed between MoSSe and CdSSe, resulting in high carrier transport efficiency. In the X-ray photoelectron spectroscopy results, the Mo and Se signals showed a large shift nearly 1 eV which confirms the strong binding between MoSSe and CdSSe. In the photoelectrochemical tests, the MoSSe/CdSSe heterojunction demonstrated a photocurrent density of -3.097 mA/cm2 at 0V (RHE) which is 2.7 and 2.9 times that of MoSSe (-1.227 mA/cm2) and CdSSe (-1.127 mA/cm2) respectively with a low resistance of 161 W. Moreover, the MoSSe/CdSSe also has good electrocatalytic hydrogen evolution performance with an overvoltage of 180 mV and Tafel slope of 69 mV/dec. Fluorescence and photocurrent response tests confirmed its higher carrier separation efficiency. This work demonstrates the application of ternary metal selenium sulfide heterojunctions in catalytic energy materials.

Keywords: MoSSe/CdSSe, heterojunction, Photoelectrochemistry, Electrocatalysis