Abstract: Using ascorbic acid as reducing agent, Cu₂O crystal was synthesized by low temperature aqueous phase method, and the different samples were prepared by controlling the mass of surfactant polyvinylpyrrolidone. The structure and morphology of the samples were characterized by X-ray diffraction, scanning electron microscope, ultraviolet visible spectrophotometer and Fourier transform infrared spectroscopy. The experimental results show that increasing the mass of PVP can change the crystal morphology and increase the exposure ratio of (111)/(200) crystal surface. The crystal plane heterojunction formed between (111) and (200) crystal planes can enhance the separation ability of photogenerated electrons and hole pairs in the photocatalytic process, thus imporving the photocatalytic efficiency of Cu₂OO crystal. Spherical Cu₂O crystal can be used as templates for the compound synthesis.

Key words: low temperature aqueous phase method, PVP mass, exposure ratio of (111)/(200) crystal plane