One-step direct synthesis of nano bismuth vanadate from bismuth oxide and sodium metavanadate via liquid phase ball-milling method: A novel and environmentally friendly process

Abstract

BiVO4 is one of most promising photocatalytic materials. In order to avoid the pollution of NOx to the environment and high-cost during the traditional synthesis process. A novel and environmentally friendly process using liquid ball-milling one step synthesis BiVO4 via NaVO3 and Bi2O3 was first proposed. The Box-Behnken (BBD) design in response surface method (RSM) was used to optimize experimental factors affecting the conversion rate of Bi2O3. Synthesis of BiVO4 from Bi2O3 and NaVO3 is completely feasible through one-step liquid phase ball milling. The optimized values of temperature, time, NaVO3 concentration, liquid-solid ratio and ball material ratio was 77.3°C, 1.85 mol/L, 1.8 h, and 17.7, respectively, obtained the conversion ratio of Bi2O3 of 92.01%. Based on one-factor-at-a-time experiments, the conversion rate of Bi2O3 reached 91.0% under the optimum synthesis conditions (T=80 °C, t=2.0 h, CNaVO3=1.0 mol/L, L/S=20 mL/g and ball to material ratio=15). Compared with the preparation of BiVO4 without ball milling, the conversion rate of Bi2O3 is increased by 64.9% via liquid phase ball-milling. Characterization via TEM and SEM showed that BiVO4 had, dendritic shape, 200-300 nm diameter, bright yellow color, and satisfactory appearance.