Strain-Induced Ferroelectric Heterostructure Catalysts of Hydrogen Production through Piezophototronic and Piezoelectrocatalytic System

In this work, we discover a piezoelectrocatalytic system composed of a ferroelectric heterostructure of BaTiO₃ (BTO)@MoSe₂ nanosheets, which exhibit piezoelectric potential (piezopotential) coupling with electrocatalyzed effects by a strain-induced piezopotential to provide an internal bias to the catalysts’ surface; subsequently, the catalytic properties are substantially altered to enable the formation of activity states. The H₂ production rate of [email?protected]₂ for the piezoelectrocatalytic H₂ generation is 4533 μmol h^–1 g^–1, which is 206% that of TiO₂@MoSe₂ for piezophototronic (referred to as piezophotocatalytic process) H₂ generation (～2195.6 μmol h^–1 g^–1). [email?protected]₂ presents a long-term H₂ production rate of 21.2 mmol g^–1 within 8 h, which is the highest recorded value under piezocatalytic conditions. The theoretical and experimental results indicate that the ferroelectric BTO acts as a strain-induced electric field generator while the few-layered MoSe₂ is facilitating piezocatalytic redox reactions on its active sites. This is a promising method for environmental remediation and clean energy development.