In this study,we investigated the production of hydrogen by photochemical water splitting.A multi-shaped Cu2O nanoparticles/MnO–MnO2 nanorods heterojunction on a few-layer graphene-based electrode serves as the photocathode.Multi-shaped Cu2O nanoparticles,including truncated cubic shape,cuboctahedral shape,truncated octahedral shape,and octahedral shape,were then coated on square manganese nanorods on a few-layer graphene-based electrode as the photosensitizer.Finally,the efficiency of hydrogen production was measured and recorded.The Cu2O nanoparticles/MnO–MnO2 nanorods heterojunction generates photoelectrons to reduce hydrogen ions into hydrogen gas.The manganese dioxide nanorods were combined with cuprous oxide multi-shaped nanoparticles to be simultaneously utilized in hydrogen production as a photochemical water-splitting solar cell.The highest rate of hydrogen generation is 33.0 mL/min m2 under solar simulation radiation.This study highlights the significance of a back electron–hole recombination loss and transportation process on the surface of a water-splitting photocathode,retarding the appearance of the photocurrent and requiring a greater amount of energy from a solar device.