Piezoelectric polarization modulated novel Bi2WO6/g-C3N4/ZnO Z-scheme heterojunctions with g-C3N4 intermediate layer for efficient piezo-photocatalytic decomposition of harmful organic pollutants

•The polarization field promotes band tilting and Bi2WO6/ZnO Z-scheme formation.•The g-C3N4 may reduce the recombination of carriers at the interface of Bi2WO6 and ZnO.•Close interface contact of Bi2WO6/g-C3N4/ZnO expands the charge transfer path.