Promoting Photocatalytic H₂ Evolution on Organic–Inorganic Hybrid Perovskite Nanocrystals by Simultaneous Dual-Charge Transportation Modulation

Organic–inorganic hybrid perovskites have demonstrated great potential in solar cell fabrication due to excellent optoelectronic properties. However, their success in solar cells has been hardly translated to producing solar fuels because of instability issues and serious charge recombination at the nanoscale domain. Herein, we show for the first time that organic–inorganic hybrid perovskite methylammonium lead bromide (MAPbBr3) nanocrystals can be stabilized in aqueous HBr solution and achieve photocatalytic H2 production reaction under visible light. More impressively, by hybridizing MAPbBr3 with Pt/Ta2O5 and poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) nanoparticles as electron- and hole-transporting motifs, respectively, drastically enhanced charge transportation on MAPbBr3 and improved catalysis were achieved. As a consequence, the rate of photocatalytic hydrogen evolution on pristine MAPbBr3 was increased by ca. 52 times by introducing dual nanoscale charge-transporting highways, achieving an apparent quantum efficiency of ca. 16.4% for H2 evolution at 420 nm.