Synthesis of CuMgAl Layered Double Hydroxides for Efficient Photocatalysis of Rhodamine B

CuMgAl layered double hydroxides CuMgAL-LDHs with different Cu/Mg/Al molar ratios have been successfully synthesized by the coprecipitation method.The structure and properties of the CuMgAL-LDHs photocatalysts were characterized by X-ray diffraction(XRD),inductively coupled plasma(ICP) and Fourier transform infrared(FTIR) spectra.The results show that the photocatalytic activity of layered double hydro-xides(LDHs) can be improved with the metal cations of appropriate proportion and species incorporated in octahedral layers of LDHs.The degradation rate with a fixed CuMgAl-LDHs dose of 3 g/L was found to be 85.2% among which the ratio of photocatalytic degradation to total degradation is over 50%,when temperature and pH were 13 ℃ and 7.84,respectively.Meanwhile,it is discovered that the pseudo-second-order kinetic equation best describes the photocatalytic kinetics of Rhodamine B on CuMgAl-LDHs.