固-固相化学反应法制备纳米铜锰复合氧化物

以碱式碳酸铜、无水碳酸锰与草酸为原料,采用固-固相化学反应法制备了纳米铜锰复合氧化物前驱物,利用正交设计考察了原料中铜与锰的摩尔比、热分解温度及时间对产物纳米铜锰复合氧化物粒径的影响。研究表明,热分解温度对产物的粒径影响最大。最小粒径产物的制备条件是:原料中铜与锰的摩尔比为 1∶2、热分解温度 400℃、热分解时间 2h。XRD和TEM分析结果表明,产物的主要物相组成为Cu0. 425Mn0. 549O2,属立方晶系,Fd3m空间群,平均粒径为 11 .7~19nm。应用TG-DTA和DSC技术研究了纳米铜锰复合氧化物的热分解过程以及热分解动力学,采用Ozawa积分法和Coats-Redfern积分法得前驱物的热分解机理函数均为G(a) = -ln(1-α) ]23。

Nanograde Cu-Mn Complex Oxides Powders Prepared by Solid-state Reaction

Precursor of Cu-Mn complex oxides nanometer powder was synthesized by solid-state reaction of Cu_2(OH)_2CO_3,MnCO_3 and H_2C_2O_4·2H_2O at room temperature.Experimental result indicates that diameter of the product is greatly affected by the decomposion temperature.The optimum conditions for preparation of the nanograde powder are m(Cu)/m(Mn)=1/2,decomposion temperature =400 ℃ and decomposion time=2 h.XRD and TEM studies show that the main product phase is Cu_(0.425)Mn_(0.549)O_2,the crystal form is cubic,the space group is Fd3m,and the average particle size is 11.7~19 nm.Besides,TG-DTA and DSC chemical reaction kinetic theory was employed here,and the Ozawa integral method and Coats-Redfern integral method were used.After the calculation and comparison,the thermal decomposition mechanical function are confirmed as the function form of -ln(1-α)]~(23).