Synergistic effect of diatomite and Bi self-doping Bi2MoO6 on visible light photodegradation of formaldehyde

Abstract

Good indoor air environment is of great significance for the health and comfort assurance of occupants. In this work, a series of bismuth self-doping Bi 2 MoO 6 /diatomite (BD-X) composites with different proportions of bismuth and molybdenum source were prepared via a mild solvothermal process. Under visible light irradiation, the BD-3 sample exhibited the optimal formaldehyde (HCHO) mineralization performance, and the corresponding calculated rate constant was up to 3.2 times higher than that of bare Bi 2 MoO 6 (B). The introduction of diatomite as catalyst carrier could not only contribute to the dispersion of nano-scale Bi 2 MoO 6 photocatalyst, but also promote the exposure of (001) crystal plane of Bi 2 MoO 6 . In particular, the molybdenum vacancy generated with increasing the proportion of bismuth source, which effectively facilitated the separation of photogenerated carriers. Moreover, the photogenerated holes (h + ) played the major role in the photocatalytic degradation process. Overall, this research would provide a novel binary composite photocatalyst derived from natural mineral for the high-efficient mineralization of formaldehyde under visible light. • An efficient adsorption-photocatalysis system was constructed with diatomite as carrier. • The molybdenum vacancy generated with increasing the proportion of bismuth source. • Diatomite and Bi self-doping Bi 2 MoO 6 promoted the synergistic photodegradation of HCHO. • Excellent photocatalytic mineralization of HCHO was obtained under visible light.