制备工艺对NiFe2O4分解CO2活性的影响

随着大气中CO2浓度的增加,温室效应日趋严重,促使人们对大气中CO2的转化与消除这一课题更加重视。1990年Yutaka Tamaura1]发现氧缺位磁铁矿几乎可以100%分解CO2后,为解决温室效应提供了一条新的探索途径。通过对不同铁酸盐MFe2O4(M=Fe,Mn2],Co3],Zn4],Ni5]等)分解CO2活性的考察,发现铁酸镍在300℃分解CO2的活性比其它铁酸盐都好。NiFe2O4的制备最常采用的是共沉淀法、柠檬酸溶胶凝胶法和水热法,3种方法由于制备

Effect of NiFe2O4 Processing Technology on Decomposition of CO2

Ultra-fine NiFe₂O₄ particles were prepared by co-precipitation, citrates sol-gel and hydrothermal methods, respectively. The relationships between decomposition of CO₂ and microstructure of NiFe₂O₄ were studied by means of XRD, H₂-TPR and low temperature N₂ sorption isotherms. The crystallite size and the pore structure of samples were different with different synthesis methods. Although all samples were nano crystals with single spinel NiFe₂O₄ structure, their H₂-reduction processes were different. NiFe₂O₄ prepared by co-precipitation methods had the smallest average crystallite size and the largest BET surface areas and showed the best decomposition activity, while NiFe₂O₄ prepared by hydrothermal method had the biggest average crystallite size and the smallest BET surface areas and the worst decomposition activity. The phases content, crystallite size and the performance on decomposing CO₂ were different for different NiFe₂O₄ according to the results of XRD Rietveld analysis.