掺Ni铁酸铋纳米粉的制备及光催化性能

Preparation and Photocatalytic Properties of Bismuth Ferrite Nano-powder Doped with Ni

采用双溶剂溶胶-凝胶法制备了一系列BiFe 1-x Ni x O 3(BFNO,x=0.00、0.02、0.04、0.06、0.08)纳米粉。X射线衍射测试结果表明,利用溶胶-凝胶法制备的BFNO粉末样品为R3C三方相结构;扫描电子显微镜图像显示,随着Ni掺杂量增加,BFNO粉末的晶粒尺寸减小;光电子能谱分析表明,BFNO中的Ni存在Ni 3+和Ni 2+两种价态,变价Ni离子作为光诱导电子和空穴的捕获位点,可以有效提高光生载流子的分离速率并降低复合速率;紫外-可见光吸收光谱分析表明,掺Ni的BiFeO 3粉末的吸收带边发生了红移,带隙呈减小趋势;磁性测量结果表明,随着Ni掺杂量的增加,BFNO铁磁性显著增强。在可见光照射下,通过BFNO纳米粉对刚果红溶液的光催化降解,分析了BFNO纳米粉的光催化活性,结果表明,随着Ni掺杂量的增加,BFNO光催化活性显著增强,Ni掺杂量为8%时样品的催化性能最强。光致发光实验表明,BFNO光催化活性增强可以归因于Ni掺杂效应导致的电子-空穴对复合效率的降低。

Different Ni-doped BFO nanoparticles(BiFe 1-x Ni x O 3,x=0.00,0.02,0.04,0.06,0.08)were prepared by double solvent sol-gel method.The results of X ray diffraction showed that the BFNO powder sample prepared by sol-gel method was R3C rhombohedra structure.The scanning electron microscope showed that the grain size of BFNO powder decreased with the increase of Ni doping amount.The photoelectron spectroscopy analysis showed that Ni in BFNO had two valence states of Ni 3+and Ni 2+.As the capture site of photo induced electrons and holes,Ni ions can effectively improve the separation rate of photo generated carriers and reduce the recombination rate.The analysis of UV-Vis absorption spectrum shows that the band gap is decreased and Ni doping also caused red-shift of the UV-Vis absorption spectra.The results of magnetic measurement show that the ferromagnetism of BFNO increases with the increase of Ni doping.The photocatalytic activity of BFNO nano powder was analyzed by photocatalytic degradation of Congo red solution by BFNO nano powder under visible light.With the increase of Ni doping amount,the photocatalytic activity of BFNO is significantly enhanced,and the sample with 8%Ni doping had the strongest catalytic performance.The results show that the enhancement of photocatalytic activity of BFNO can be attributed to the decrease of electron hole pair recombination efficiency caused by Ni doping.