CoP-Enhanced CaTiO3 Single-Electron Oxygen Reduction Piezoelectric Catalysis for H2O2 Production

Piezoelectric catalytic production of H 2 O 2 is a novel and environmentally friendly H 2 O 2 production method, and many piezoelectric catalysts are currently being developed. However, all of them have the disadvantages of precious metals as cocatalysts and low catalytic efficiency. Herein, CaTiO 3 was successfully prepared and loaded with the nonprecious metal CoP (CoP/CaTiO 3 ) for piezoelectric catalytic production of H 2 O 2 . The yield of H 2 O 2 produced by 5% CoP/CaTiO 3 piezoelectric catalysis reached 9657.3 μmol L –1 g –1, which was 1.64 times than that of single-component CaTiO 3, and furthermore, the performance remained stable after five cycles. This study directly demonstrates the piezoelectric response of CoP/CaTiO 3 by using Piezoresponse Force Microscopy. Under ultrasonic conditions, CoP/CaTiO 3 undergoes polarization, resulting in the generation of electrons (e – ) and holes (h + ). The e – undergoes a two-step single-electron reaction with O 2 to form H 2 O 2 . Because the conduction band position of CoP is lower than that of CaTiO 3, this potential difference promotes the migration of e – from CaTiO 3 to CoP. This migration process effectively enhances the spatial separation of e – and h +, which significantly improves the piezoelectric catalytic performance. In this work, a nontoxic and inexpensive new piezoelectric catalytic material was synthesized by a method that can produce catalysts in large quantities, and a strategy was provided to improve the piezoelectric catalytic activity, which played a key role in promoting the green industrial production of H 2 O 2 .