One-step synthesis of composite material MWCNT@BiVO4 and its photocatalytic activity

Abstract

In this research, a composite material (MWCNT@BiVO₄) was prepared using a one step hydrothermal method. The prepared composite material was characterized by energy-dispersive X-ray analysis, X-ray diffraction, scanning electron microscopy, EDS, UV-Vis diffuse-reflectance spectroscopy, electron spin resonance (ESR), X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The scanning electron microscopic images showed that MWCNTs were successfully embedded into BiVO₄. MWCNT@BiVO₄ showed a strong visible-light absorption capacity, high efficiency for electron–hole separation, and excellent stability. The degradation test of RhB was conducted under visible light irradiation. Compared with BiVO₄ (K = −0.05657) and P25 (K = −0.03227), MWCNT@BiVO₄ (K = −0.11894) realized the highest removal ratio of Rhodamine B (RhB) under visible light irradiation, therefore, MWCNT@BiVO₄ might be promoted to practical applications. The stability of MWCNT@BiVO₄ was also verified via recycling and reusing experiments. After 5 cycles, MWCNT@BiVO₄ could still maintain the removal rate of RhB at 95.96%. In addition, this paper deduced the growth mechanism of MWCNT@BiVO₄ and the degradation mechanism of RhB, proving that MWCNT@BiVO₄ can be used in future practices.