关键词: 氧化锌, 光催化, 共掺杂, 稀土金属铈与钕, 罗丹明B

Abstract:

Nanoscale semiconductor photocatalytic materials were prepared by hydrothermal synthesis method.Lanthanides were ideal metal dopants,because of their unique optical properties and not fully occupied 4f orbitals,and doping lanthanides could improve the activity of catalysts.Recent studies had shown that photocatalysts could be more effectively improved by co-doping two rare earth elements,which could not only effectively improve the light absorption capacity of the catalysts through synergistic effects,but also inhibit the recombination of photogenerated carriers.The modified semiconductor ZnO photocatalytic materials were prepared by co-doping the two elements of cerium and neodymium.The prepared photocatalytic materials were analyzed and characterized by XRD,SEM,XPS,EDS,BET,UV-vis and PL,and high-performance modified photocatalysts with narrower band gap,larger specific surface area and smaller grain size were obtained.It was applied to the experiment of degrading rhodamine B simulated pollutants in wastewater,and the results showed that the degradation rate of zinc oxide doped with 2% Ce and 5.5% Nd reached 92.2% at 40 min and 98.3% at 60 min.The overall catalytic performance was greatly improved compared with single-doped Ce and single-doped Nd.The reasons for the co-doping of rare earth metals cerium and neodymium to improve the photocatalytic performance of ZnO was included:the distortion of ZnO lattice,the generation of impurity energy and the influence of rare earth ion valence,the influence of morphology and specific surface area,the band gap and the generation of rare earth ion redox pairs,etc.

Key words: zinc oxide, photocatalysis, co-doping, rare earth metals of cerium and neodymium, Rhodamine B