The effects of precursors and loading of carbon on the photocatalytic activity of C–BiVO4 for the degradation of high concentrations of phenol under visible light irradiation

Abstract

A series of carbon modified BiVO4 (C–BiVO4) photocatalysts were synthesized by impregnation calcination method of BiVO4 with glucose, sucrose and cellulose as precursors, respectively. The prepared photocatalysts were characterized by XRD, HR-TEM, SEM, Raman, BET, UV–vis DRS and PL. Their photocatalytic activities were investigated by degradation of phenol under the visible light. The precursor and loading of carbon had remarkable effects on physical–chemical properties of samples and degradation activities of phenol. The increase of the number of carbon ring in precursors led to a better crystallinity, smaller grain size, larger surface area and higher separation efficiency of electron–hole pairs. The increase of loading led to a smaller catalyst grain size, larger surface area, higher visible light absorption and higher separation efficiency of electron–hole pairs. The results showed that the 0.5wt.% of C–BiVO4–cellulose has the best photocatalytic activity and degraded 88.7% of 5mg/L phenol. Besides, addition of 25mmol KBrO3 as an electron capture agent can degrade 27.4% of 1000mg/L phenol. The degradation efficiency of the same system above mentioned under sunlight irradiation was 22.6%. In addition, the relationship between the photocatalytic activity of C–BiVO4 and its physical–chemical properties was also discussed.