Preparation and enhanced photocatalytic properties of Cu₃₁S₁₆/Cu₉S₅ heterojunction composite

Abstract

A heterojunction photocatalytic material Cu₃₁S₁₆/Cu₉S₅ was successfully synthesized through a facile solvothermal method by controlling the reaction temperature. The phase composition, morphology, absorbance and surface area were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis diffusion reflection and Brunauer–Emmett–Teller (BET). Transient photocurrent response and electrochemical impedance spectroscopy (EIS) were measured to support the generation and transfer of the photoinduced charge carriers. The heterojunction Cu₃₁S₁₆/Cu₉S₅ showed superior separation efficiency of the photoinduced charge carriers. The photocatalytic performance of the Cu₃₁S₁₆/Cu₉S₅ was evaluated through degrading high-concentration methyl orange (MO) solution under visible light. The degradation rate of MO solution increased to 94.8% in 60 min, showing the most remarkable photocatalytic ability. Moreover, a probable photocatalytic mechanism of the Cu₃₁S₁₆/Cu₉S₅ was discussed.

GRAPHICAL ABSTRACT

KEYWORDS:

• Cu₃₁S₁₆/Cu₉S₅
• solvothermal method
• heterojunction
• photocatalysis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China [Grant No. 201011809], the Natural Science Foundation of Shaanxi Province of China (No. 2020JM-510, No. 2020JQ-713) and the Foundation of Shaanxi Educational Committee (No. 21JK0535).