Efficient Piezo-Photocatalysis via g-C₃N₄/Ti₃C₂Tₓ Heterojunction: Synergy of Piezoelectric and Built-in Field

Abstract

Piezo-photocatalysis presents an innovative approach by integrating piezoelectric and photocatalytic effects, offering enhanced efficiency for sustainable renewable energy production and pollution control. In this work, we report for the exploration of piezo-photocatalytic properties of the g-C3N4/Ti3C2Tx heterojunction composite, developed via an ingenious electrostatic self-assembly method. This approach enables precise optimization of mass ratios between g-C3N4 and Ti3C2Tx to fully harness their synergistic photo/piezoelectric properties. The synthesized composite exhibits a high specific surface area, enhanced charge transfer capability, and superior piezo-photocatalytic activity. Specially, the optimized g-C3N4/Ti3C2Tx composite achieves complete degradation of rhodamine B (RhB) in just 20 minutes under piezo-photocatalytic conditions, with a high rate constant of 0.1774 min-1, which is 2.8 times and 84.48 times higher than those under pure photocatalysis and piezocatalysis, respectively. The synergistic interaction between the piezoelectric polarization field and the built-in electric field of the heterojunction significantly enhances charge separation and catalytic efficiency. The developed catalyst exhibits stable recyclability and high sensitivity to mechanical stress, making it highly promising for environmental remediation and advanced wastewater treatment applications.