CuS anchored onto peanut-like BiVO4 p-n heterojunction with enhanced photocatalytic degradation activity under visible light irradiation

Abstract

• Peanut-like CuS/BiVO 4 p-n heterojunctions were prepared by two-step hydrothermal method. • CuS/BiVO 4 composites exhibit high activity of glyphosate degradation under visible light. • The reaction rate constant of 8%CuS/BiVO 4 is 3.8 times greater than that of BiVO 4 . • CuS/BiVO 4 strongly promotes the separation of photoexcited electron and hole pairs. Seeking cheap photocatalysts for practical application is a great challenge. It is greatly significant to construct heterojunctions for the efficient separation of photoexcited carriers. Herein, a peanut-like CuS/BiVO 4 p-n heterojunction is prepared using thiourea as the raw material via a two-step hydrothermal process. The 8%CuS/BiVO 4 composite has many advantages, including excellent visible light absorption capacity, photoelectric performance, and enhanced glyphosate degradation rate by 3.8 times compared to BiVO 4 . The probable photocatalytic mechanism is proposed according to the XPS, DRS, photocurrent, PL, and experimental results. The intimate interface contact between CuS and BiVO 4 effectively achieves quick separation of photoinduced charge carriers and improves photocatalytic activity, thus enhancing degradation efficiency of glyphosate. The glyphosate degradation path is also investigated according to the intermediates detected by mass spectrometry.