Synthesis and Optimization of Visible Light Active BiVO₄ Photocatalysts for the Degradation of RhB

Table 2

Synthesis methods used and relevant parameters for the preparation of various BiVO₄ samples.

Sample (sample name)	Synthesis method	Reactants	pH of precursor slurry; (pH control medium)	Treatment temperature & time
BiVO4 (Co-pre-350-24)	Coprecipitation [19]	30 mmol Bi(NO3)3·5H2O; 30 mmol NH4VO3; 4 M HNO3; 2 M NH4OH; 9% (sodium carboxymethylcellulose) CMC^a	9 (2 M NH4OH)	Calcination at 350°C, 24 h.
BiVO4 (Comb-500-3)	Combustion [30]	2 mmol Bi(NO3)3·5H2O; 2 mmol citric acid; 1 M HNO3; 2 mmol NH4VO3; 5 mmol citric acid	7.5 (2 M NH4OH)	Calcination at 500°C, 3 h.
BiVO4 (Calc-450-5)	Calcination [24]	1 mmol Bi(NO3)3·5H2O; 3 mmol K2CO3; 5 mmol V2O5	1 (no pH adjustment)	Calcination at 450°C, 5 h.

9% CMC weight percentages related to the total weight of prepared samples.
Samples prepared via coprecipitation synthesis were denoted by the nomenclature BiVO₄ (Co-pre-YYY-YY), where YYY and YY refer to the treatment temperature and time, respectively; BiVO₄ (Comb-YYY-YY) and BiVO₄ (Calc-YYY-YY) denote samples prepared via combustion and calcination, respectively.