摘要
We develop a porous ferroelectric high-entropy oxide (HEO) by tuning the Ca concentration in (Ca x ZrYCeCr)O 2 (x = 0.09–0.5). Time-resolved photoluminescence indicates that the ferroelectric HEO sample containing 38 at% Ca atoms (38HEO) exhibits a long carrier lifetime of approximately 66 ns, 163% of the lifetime of Zr 0.3 Y 0.3 Ce 0.3 Cr 0.09 O 2 . The theoretical calculation reveals that the porous HEO into which ferroelectric Ca(Zr 0.95 Cr 0.5 )O 3 nanoparticles are embedded, separating electron-hole pairs efficiently and provides trapping centers in the piezocatalytic process, considerably prolonging the carrier lifetime. The reaction rate constant of 38HEO for the decomposition of dye molecules is 1000% of that for pristine ZrYCeCrO 2 . The hydrogen evolution reaction with polarized 38HEO resulted in hydrogen production of 677 μmolg −1 h −1 , 163% that of unpolarized 38HEO. The piezopotential of the ferroelectric Ca(Zr 1−x Cr x )O 3 was strongly coupled with the charge transfer of the HEO's surface, enhancing the catalytic activity. The concepts reported herein can be used to design next-generation piezo-photocatalysts.