Orthogonal Charge Transfer by Precise Positioning of Silver Single Atoms and Clusters on Carbon Nitride for Efficient Piezocatalytic Pure Water Splitting

Developing efficient piezocatalytic systems for two-electron water splitting (TEWS) with producing H-2 and H2O2 shows great promise to meet the industrial demand. Herein, Ag single atoms (SAs) and clusters are co-anchored on carbon nitride (AgSA+C-CN) to serve as the multifunctional sites for efficient TEWS. The Ag SAs enhance the in-plane piezoelectric polarization of CN that is intimately modulated by the atomic coordination induced charge redistribution, and Ag clusters afford strong interfacial electric field to remarkably promote the out-of-plane migration of piezoelectrons from CN. Moreover, AgSA+C-CN yields a larger piezoresistive effect that elevates carrier mobility under strain. Consequently, a superior H-2 and H2O2 evolution rate of 7.90 mmol g(-1) h(-1) and 5.84 mmol g(-1) h(-1) is delivered by AgSA+C-CN, respectively, far exceeding that of the previously reported piezocatalysts. This work not only presents the SAs decoration as an available polarization enhancement strategy, but also sheds light on the superiority of multi-sites engineering in piezocatalysis.

Automated summary

In this study, efficient piezocatalytic systems for two-electron water splitting with producing H-2 and H2O2 were developed using Ag single atoms and clusters co-anchored on carbon nitride. Ag single atoms enhanced the in-plane piezoelectric polarization, while Ag clusters promoted the out-of-plane migration of piezoelectrons. Additionally, the system exhibited a larger piezoresistive effect, leading to increased carrier mobility. As a result, the system demonstrated superior H-2 and H2O2 evolution rates compared to previously reported piezocatalysts.