催化电极材料La-Sr-Co-Fe的制备与表征

Preparation and characterization of perovstike-type catalytic electrode material of La-Sr-Co-Fe

用湿化学、共沉淀、溶胶 凝胶三种不同的制备方法,在较低焙烧温度和较短焙烧时间的实验条件下,制备了钙钛矿型La Sr Co Fe(LSCF)复合氧化物,并通过热重/差热(TG/DTA)分析、X射线衍射(XRD)分析和扫描电镜(SEM)测试等表征手段对La Sr Co Fe电极粉料进行了表征和分析。通过对催化剂活性测试表明,以溶胶 凝胶法制备的催化剂活性最高。TG/DTA、XRD分析结果表明以溶胶 凝胶法制备的催化剂母体在三种不同制备方法中在最低的温度下形成钙钛矿晶型。且XRD分析结果表明,La Sr Co Fe电极粉料完全形成了单一的钙钛矿晶型,而无单独的氧化物晶相存在。从SEM可以看出,溶胶 凝胶法制备的催化剂颗粒均匀,结构疏松,比表面积大,有利于LSCF的催化氧化活性的提高。

The La-Sr-Co-Fe (LSCF) series catalysts that prepared by wet-chemistry, co-precipitation, sol-gel methods were characterized and analyzed by TG/DTA, X-ray diffraction (XRD), as well as scanning electron micrograph (SEM). The catalysts prepared by sol-gel method present the best activity. The TG/DTA results show that the LSCF precursor prepared by sol-gel method forms the perovskite crystal in the lowest temperature among the three methods because the LSCF precursor is in good dispersion. XRD patterns show that all the catalysts form the perovskite structure perfectly and the single oxide does not exist. SEM shows that the catalysts prepared by sol-gel method have proper porosity and surface area and can provide more active center to improve its catalytical oxidation activity.