形貌控制合成介孔纤维状钴酸镍粉末  

Morphology-controlled Synthesis of Mesoporous Fibrous NiCo_2O_4 Powders

作　　者：马雅琳 陆二聚 湛菁 刘恢 

机构地区：[1]中南大学冶金与环境学院,湖南长沙410083

出　　处：《矿冶工程》2017年第4期112-116,共5页Mining and Metallurgical Engineering

基　　金：国家自然科学基金青年基金(51404306);湖南省科学技术厅科技计划(2010FJ3012);佳纳研究基金(JNJJ201613)

摘　　要：以可溶性氯化镍、氯化钴和草酸为原料,利用氨为配位剂,通过配位共沉淀-热分解法制备了多孔纤维状钴酸镍(NiCo_2O_4)粉末。采用XRD、SEM、TEM、IR以及BET对前驱体和NiCo_2O_4粉末的物相、成分与形貌进行了表征,系统考察了配位共沉淀条件对前驱体粉末形貌、粒度和成分的影响。采用DTA/TG研究了钴酸镍前驱体粉末的热分解历程。结果表明:Ni^(2+)-Co^(2+)-NH_3-NH_4^+-C_2O_4^(2-)-H_2O反应体系中,在溶液pH=8.0、温度50℃、金属离子浓度0.5 mol/L的条件下可得到纤维状钴酸镍前驱体粉末;氨与镍钴离子配合生成含氨草酸镍钴复盐是纤维状形貌形成的机理。在空气气氛中300℃热分解该前驱体粉末即可得到比表面积97 m^2/g、平均孔径11 nm、轴径比30~50的纤维状多孔NiCo_2O_4粉末。Mesoporous fibrous NiCo2O4 powders were synthesized by coordination co-precipitation and thermal decomposition using soluble nickel chloride,cobalt chloride and oxalate as starting materials and ammonia as a complexing agent.The phase,composition and morphology of the precursor and NiCo2O4 were characterized by XRD,SEM,TEM,IR and BET analysis.The influences of coordination co-precipitation conditions on the morphology,composition and size of the precursor particles were investigated.The thermal decomposition process of nickel cobaltate precursor was studied by DTA/TG analysis.Results showed that fibrous nickel cobaltate precursor powders could be obtained from the reaction system of Ni2＋-Co2＋-NH3-NH4＋-C2O42--H2O under the conditions of pH = 8.0,temperature of 50 ℃ and metal ion concentration of 0.5 mol/L.The coordination of ammonia with nickel and cobalt ions resulted in oxalate-ammonia complex salt,indicating an intrinsic mechanism of the formation of fiber-like morphology.The mesoporous fibrous NiCo2O4 powders with specific area of 97 m2/g,an average pore diameter of 11 nm and an axis/diameter ratio of 30 50 can be produced by thermal decomposition of the precursor at 300 ℃ in air.

关 键 词：钴酸镍 纤维状 配位共沉淀 形貌控制 

分 类 号：O614.81[理学—无机化学]