The Mechanism of Piezocatalysis: Energy Band Theory or Screening Charge Effect?

Piezocatalysis, a new-emerging catalysis technology relying on catalyst's piezopotential and piezoelectric property, is attracting unprecedented research enthusiasm for applications in energy conversion, organic synthesis, and environmental remediation. Despite the rapid development in the past three years, the mechanism for piezocatalysis is still in debate. A fundamental understanding of the working principles should be enhanced to further advance this technology for future piezocatalysts design and system optimization. In this article, we review the two popular theories to explain the observed piezocatalysis in terms of the energy band theory and the screening charge effect. A comprehensive discussion and clarification of the difference, relevance, evidence and contradiction of the two mechanisms is provided. Finally, the challenges and perspectives of the future mechanic study are put forward. Hopefully, this review can help readers to gain a better understanding and to start quickly in applying piezocatalysis to their own research.