微米级CuFe/CuFeO2的制备及其类Fenton催化性能

摘要

采用两步法,采用水热法以Fe(NO3)3·9H2O、Cu(NO3)2·SH2O作为前驱体,水为溶剂,正丙醛为还原剂,制备了CuFeO2微米颗粒.为进一步提高其催化活化H2O2的性能,使用硼氢化钠对其进行了还原处理制备微米CuFe/CuFeO2催化剂.利用XRD、SEM和XPS对其进行了物相,形貌和表面元素的表征,结果表明所制备的材料为Cu、Fe和CuFeO2的微米级复合物.以罗丹明B(RhB)为目标污染物,评价了其Fenton催化性能.结果表明:在25℃,CuFe/CuFeO2催化剂用量为0.5 g/L,H2O2浓度为40 mmol/L,RhB浓度为10μmol/L,初始pH=5.0时,CuFe/CuFeO2催化剂在30 min内可降解94.4％的RhB,表观速率常数是相同条件下未处理CuFeO2的11.6倍.这说明CuFe和CuFeO2复合可明显增强其催化活化H202的能力.%CuFe/CuFeO2 micro-composites were prepared via a two-step route.CuFeO2 microparticles were first prepared through a modified hydrothermal method with Fe(NO3)3· 9H2O and Cu(NO3)2·5H2O as precursors in the presence of distilled water and propionaldehyde,and then CuFe/CuFeO2 micro-composites were obtained from the controllable reduction of the as-prepared CuFeO2 microparticles by NaBH4.The structure,morphology and surface element composition of CuFe/CuFeO2 micro-composites were characterized by X-ray diffraction,scanning electron microscopy and X-ray photoelectron spectroscopy.It was found that as-prepared products were a microscaled composite of Cu,Fe and CuFeO2.The Fenton-like catalytic activity of CuFe/CuFeO2 micro-composites was evaluated via the degradation of rhodamine B (RhB) as a model pollutant.It was found that 94.4％ RhB (10 μmol/L) can be degraded in 30 min at initial pH 5.0 and concentration of 0.5 g/L CuFe/CuFeO2 and 40 mmol/L H2O2.The first-order reaction kinetic constant for the degradation of RhB by CuFe/CuFeO2 is 11.6 times that by CuFeO2.These results show that the H2O2-activating ability of CuFe/CuFeO2 significantly enhances by the composite of CuFe and CuFeO2.