Piezoelectricity

Charge carrier

Nanotechnology

Organic chemistry

Hydrogen bromide

Hydrogen

Photocatalysis

Engineering

Perovskite (structure)

Catalysis

Photocatalytic water splitting

Composite material

Hydrogen production

Halide

Inorganic chemistry

Chemistry

Metallurgy

Materials science

Bromine

Water splitting

Chemical engineering

Optoelectronics

Photochemistry

Advanced Energy Materials

To alleviate photoinduced charge recombination in semiconducting nanomaterials represents an important endeavor toward high‐efficiency photocatalysis. Here a judicious integration of piezoelectric and photocatalytic properties of organolead halide perovskite CH 3 NH 3 PbI 3 (MAPbI 3 ) to enable a piezophotocatalytic activity under simultaneous ultrasonication and visible light illumination for markedly enhanced photocatalytic hydrogen generation of MAPbI 3 is reported. The conduction band minimum of MAPbI 3 is higher than hydrogen generation potential (0.046 V vs normal hydrogen electrode), thereby rendering efficient hydrogen evolution. In addition, the noncentrosymmetric crystal structure of MAPbI 3 enables its piezoelectric properties. Thus, MAPbI 3 readily responds to external mechanical force, creating a built‐in electric field for collective piezophotocatalysis as a result of effective separation of photogenerated charge carriers. The experimental results show that MAPbI 3 powders exhibit superior piezophotocatalytic hydrogen generation rate (23.30 µmol h −1 ) in hydroiodic acid (HI) solution upon concurrent light and mechanical stimulations, much higher than that of piezocatalytic (i.e., 2.21 µmol h −1 ) and photocatalytic (i.e., 3.42 µmol h −1 ) hydrogen evolution rate as well as their sum (i.e., 5.63 µmol h −1 ). The piezophotocatalytic strategy provides a new way to control the recombination of photoinduced charge carriers by cooperatively capitalizing on piezocatalysis and photocatalysis of organolead halide perovskites to yield highly efficient piezophotocatalysis.

Remarkably Enhanced Hydrogen Generation of Organolead Halide Perovskites via Piezocatalysis and Photocatalysis