Rational Design of 0D/2D WO₃/g‐C₃N₄ Z‐scheme Hybrid for Improving Photocatalytic Dye Degradation

Abstract

A Zero-dimensional/two-dimensional (0D/2D) tungsten trioxide/graphitic carbon nitride (WO 3 /g-C 3 N 4 ) Z-scheme hybrid was prepared by employing a simple calcination process. Then, the photocatalytic property of the WO 3 /g-C 3 N 4 hybrids was assessed through their efficiency in the degradation of toxic industrial dye pollutant, Rhodamine B (RhB) and phenol under visible light irradiation. From the results and analysis, the 1 % WO 3 /g-C 3 N 4 composite with a larger Brunauer-Emmett-Teller (BET) surface area of 41.14 m 2 g À 1 compared to the pristine g-C 3 N 4 (25.25 m 2 g À 1 ) presented the uppermost improvement in the photocatalytic performance contrasted to both WO 3 and g-C 3 N 4 . It achieved the degradation of RhB and phenol with an efficiency of 96 % in 15 min and 98.5 % in 30 min, respectively. X-ray photoelectron spectroscopy (XPS) results confirmed the existence of the internal electric field. The enhanced activity was attributed to the homogeneous distribution of the WO 3 nanoparticles on the g-C 3 N 4 nanosheets with intimate interface and matched band gap structure which favored the construction of the Z-scheme hybrid, therefore boosting the electronhole separation efficiency and maintaining the strong redox capability for photocatalytic degradation.

2D/1D Z-scheme WO3/g-C3N4 photocatalytic heterojunction with enhanced photo-induced charge-carriers separation

“…Therefore, it is commonly adopted to form Z-scheme heterojunctions with semiconductors which have low valance band maximum (VBM). Previous studies have confirmed that WO 3 is an appropriate semiconductor to construct Z-scheme heterojunction with g-C 3 N 4 , which exhibits well-matched band structure [6][7][8][9][10][11][12]. Currently most WO 3 /g-C 3 N 4 heterojunctions reported are based on twodimensional (2D) g-C 3 N 4 nanosheets [13,14], and there are few researches focusing on one-dimensional (1D) g-C 3 N 4 nanotubes which actually show good photocatalytic activity.…”

Recent Progress on Photoelectrochemical Water Splitting of Graphitic Carbon Nitride (g−CN) Electrodes

“…Other than the recombination with UV-active TiO 2 and ZnO semiconductor, WO 3 has received prodigious attention as a promising candidate owing to its relatively lower band gap (2.5–2.8 eV), which lies in the visible-light range, thus increasing the potential for wider utilize in the PEC applications [ 192 , 193 , 194 ].…”