尖晶石CoAl_2O_4光催化还原CO_2的研究

采用无机盐溶胶-凝胶法制备了CoAl2O4纳米粉体,用紫外-可见分光光度计(UV-Vis)、X射线衍射光谱仪(XRD)和扫描电子显微镜(SEM)对其光电活性、晶体结构和形貌进行了表征。结果表明,所制备催化剂属尖晶石结构,颗粒呈近球形和不规则形状,粒子尺寸约4.39 nm,光吸收极限波长大于800 nm,计算得到禁带宽度Eg1.55 eV。在高压汞灯照射下,分别选用K2C2O4、NaHSO3和NaH2PO2为供电子试剂,进行了光催化还原CO2制取甲酸的研究。结果表明,在选用NaHSO3的情况下,CoAl2O4的催化效果最好,光照4 h,甲酸产量达到4004.16μmol/g-Cat。

Study on Photocatalysis Reduction of CO2 Using Spinel CoAl2O4

Spinel nano-particles of CoAl2O4 were prepared by the inorganic salt sol-gel method in the paper,the absorbency,crystalloid structure and morphology of the prepared samples were described using analytic technologies such as UV-Vis,XRD and SEM.The investigation showed that this photocatalyst with particle sizes of 4.39nm exhibited a spinel-type structure.They were the near-sphericity and abnormity granules.The maximum wavelength of absorption was exceeded at 800nm.The band gap was calculated less than 1.55eV.The photocatalysis reduction on synthesis of HCOOH form CO2 and H2O was investigated under the irradiation of the pressure hydrargyrun lamp by using K2C2O4,NaHSO3 and NaH2PO2.The investigation showed that CoAl2O4 had better activity.Methanoic acid yield may achieve 4004.16μmol/g-Cat by using the NaHSO3 when irradiation time was 4h.