Relationship between Planes of Cu<sub>2</sub>O Microcrystal and Photo-Catalytic Degradation of Methylene Blue

Abstract

Four kinds of Cu2O microcrystals with different morphologies are synthesized via low temperature hydrothermal synthetic method. The photocatalytic degradation of methylene blue (MB) of the above different Cu2O is preliminary explored based on this observation. 6-facet, 8-facet, 14-facet are prepared by PVP system and 26-facet is prepared by NaOH system. They are characterized by means of Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Diffuse Reflectance Spectra (DRS). Under 150 W xenon lamp irradiation, 0.5 gL1 catalyst and 0.1% (v/v) 30% H2O2 as co-catalyst are used to degrade 5% 100 mL MB solution. The reaction time is 80 min. 26-facet Cu2O polyhedral discolor about 89.48% of MB while 6-facet Cu2O microcrystal about discolor about 20.18% which is the lowest decolourization rate among all the samples. The photocatalytic performance of 8-facet Cu2O microcrystal is slight better than that of 14-facet. The decolourization rate of 8-facet and 14-facet are 56.00% and 41.08%, respectively. The main reason is that the planes of Cu2O microcrystal have a main influence on photocatalytic degradation of MB.