共沉淀法制备La_(2-x)Sr_xCuO_4及LaSrCu_(1-y)W_yO_4

The Study on Perovskite Catalyst La_(2-x)Sr_xCuO_4 and LaSrCu_(1-y)W_yO_4 Prepared by Coprecipitation

采用共沉淀法制备钙钛矿氧化物La_(2-x)Sr_xCuO_4及LaSrCu_(1-y)W_yO_4,通过X-射线衍射(XRD)、比表面测定仪(BET)等技术测试钙钛矿样品的晶体结构及比表面积.XRD测试结果表明,对于La_(2-x)Sr_xCuO_4类钙钛矿型氧化物,随着Sr掺杂量的增加,钙钛矿结构的物质杂峰会有所增多;此外,对于LaSrCu_(1-y)W_yO_4而言,W掺杂量对钙钛矿氧化物的晶型结构的影响较小.比表面实验表明,无论是A位元素部分调整还是B位元素部分取代,La_(2-x)Sr_xCuO_4及LaSrCu_(1-y)W_yO_4的比表面积都有明显的增加,但是当比例达到某一值后反而会有所下降。

The perovskite composite oxide La2-xSrx CuO4 and LaSrCu1-y WyO4 were prepared by coprecipitation. The structures of perovskite catalysts and the influence of strontium or tungsten loading on perovskite crystal structure were investigated using X-ray scattering （XRD）. The specific surface areas were determined by Brunauer-Emmet-Teller （BET）. The XRD results showed that the perovskite structure of the material increased with the increasing of the strontium loading for La2-xSrxCuO4 perovskite catalyst. In addition, for LaSrCu1-yWyO4 perovskite catalyst, the wolfram loading does not effect the perovskite crystal structure of the catalyst. The BET results indicated that the surface areas of La2-xSrxCuO4 and LaSrCu1-yWyO4 increased with choice of A-site and B-site elements but then decreased.