化学共沉淀法制备气敏材料Cd2+XSb2O6.8

采用化学共沉淀法，以可溶性的镉盐和三价锑盐为源物质、氢氧化物作共沉淀剂，在较宽的Cd/Sb摩尔配比范围内，制备出了具有缺陷烧绿石结构的镉锑复合氧化物Cd₂Sb₂O_6.8及其固溶体。研究了烧成条件对产物的影响，在较低温度(600℃)下得到了纯相Cd₂Sb₂O_6.8的超微粉，并对其高温反应机理进行了探讨。所得微粉产物制成的厚膜元件经气敏测试，发现n(Cd)/n(Sb)=1.10、 900 ℃、3 h烧成的间隙型固溶体Cd_2+XSb₂O_6.8，对乙炔气体具有非常优秀的气敏性能。

THE GAS-SENSING MATERIAL Cd2+XSb2O6.8 MADE BY CHEMICAL COPRECIPITATION

he ultramicro powders of the complex oxide Cd\-2Sb\-2O\-\{6.8\} and its solid solutions, with defect pyrochlore structures, were prepared by a modified chemical coprecipitation method, using a caustic alkali as the precipitant and solvable cadmium and trivalent antimony salts as the precursors. The effects of preparation conditions on the product phase compositions and structures were also studied. The pure Cd\-2Sb\-2O\-\{6.8\} phase could be obtained at a low calcining temperature (600), and a hightemperature reaction mechanism was proposed to explain it. The gassensing properties of the thick film elements based on the various product powders were tested. It is found that the interstitial solid solution Cd\-\{2 X\}Sb\-2O\-\{6.8\}, made with n(Cd)/n(Sb)=1.10 and calcined at 900 for 3 h, shows to be an excellent gassensing material.