Tandem Fields Facilitating Directional Carrier Migration in Van der Waals Heterojunction for Efficient Overall Piezo‐Synthesis of H₂O₂

Abstract

Piezo‐synthesis of H2O2 utilizing sustainable mechanical energy as well as earth‐abundant water and oxygen is a green, cost‐effective and promising approach. However, achieving simultaneous two‐electron water oxidation reaction (2e− WOR) and two‐electron oxygen reduction reaction (2e− ORR) faces huge challenges due to insufficient synergistic active sites and slow/messy carrier transfer. Herein, a novel 2D/2D van der Waals (vdW) heterojunction consisting of BiOIO3 and carbon nitride (BIO/CN) was elaborately designed for highly efficient overall H2O2 piezo‐synthesis. Theoretical/experimental results revealed that a Z‐scheme electron transfer was formed and facilitated by the tandem interfacial electric field and the bulk piezo‐polarization field. On this basis, the carriers are efficiently separated while the oxidation/reduction capacity is preserved, thus providing strong driving force for the 2e− WOR and 2e− ORR on BIO and CN, respectively. Furthermore, the kinetic and thermodynamic process of WOR and ORR for H2O2 synthesis improved remarkably. Therefore, BIO/CN exhibits an excellent H2O2 yield of 259.8 μM within 30 min in pure water and air atmosphere (without any sacrificial agents and aeration). This study provides a new idea on strategically controlling electron transfer towards high‐efficiency H2O2 piezo‐synthesis and expands the avenue for developing effective environmental purification materials.This article is protected by copyright. All rights reserved