Catalysis Today, Vol.325, 41-46, 2019
Photocatalytic activity of the (NH4)(2)V6O16/g-C3N4 composite catalysts for water splitting applications
A hydrothermal method was used to prepare a lozence shape like (NH4)(2)V6O16 photocatalyst to split water into hydrogen. The energy gap of the (NH4)(2)V6O16 is about 2.7ev and the absorption wavelength is about 350-800 nm. In order to modify and enhance the photocatalytic reactivity of the (NH4)(2)V6O16, a graphitic carbon nitride (g-C3N4) possessing higher of lone pairs that can excite electron to combine with H+ and decrease electron-electronic hole recombination was added into the lozence shape like (NH4)(2)V6O16 to form a composite material. Thus, the synsthesis of the lozence shape like (NH4)(2)V6O16/g-C3N4 photocatalysts were controlled by the pH value, hydrothermal temperature, and the g-C3N4 concentration. For the photocatalytic reactivity of catalysts, a self-assemble reactor equipped with GC-TCD is used to analyze the water splitting efficiency. The optimum conditions to synthesize pure (NH4)(2)V6O16 are the acidic environment of pH = 3, the hydrothermal temperature of 200 degrees C, and the hydrothermal time of 4 h. The optimum concentration of g-C3N4 in the (NH4)(2)V6O16/g-C3N4 composite is 14 wt% and the accumulative concentration of hydrogen production reaches to the highest value of 2300 mu mol/g cat.