Haiwen Wang
材料科学技术(英文)
Indium tin oxide (ITO) nanoparticles with crystallite size of 12.6 nm and specific surface area of 45.7 m2·g-1 were synthesized by co-precipitation method. The indium solution was obtained by dissolving metal indium in HNO3. The tin solution was obtained by dissolving metal tin in HNO3 and followed by stabilizing with citric acid. The free of chlorine ions in the synthesis process brought several advantages: shortening the synthesis time, decreasing the particle agglomeration, decreasing the chlorine content in the ITO nanoparticles and improving the particle sinterability. This is the first time to report the synthesis of ITO nanoparticles free from chlorine contamination without using the expensive metal alkoxides as starting materials.
关键词:
Nanomaterials
,
Powder technology
,
Indium tin oxide
,
Coprecipitation method
谭鹏甲
,
高志华
,
沈朝峰
,
杜亚丽
,
李晓东
,
黄伟
催化学报
doi:10.1016/S1872-2067(14)60171-6
采用表面活性剂辅助共沉淀法制备了Ni-Mg-Al固体碱催化剂并用于CH4-CO2重整反应,探讨了表面活性剂对Ni(111), Ni(200)晶面的择优取向作用,在800°C下比较了不同表面活性剂制备的催化剂的催化性能,详细考察了CTAB制备的催化剂CB-LDO在不同反应温度下的催化活性和稳定性。采用红外光谱、X射线衍射、程序升温还原、X射线光电子能谱、高分辨透射电镜和程序升温氧化等表征手段分析了催化剂的活性、稳定性和失活原因。结果表明,四丙基氢氧化铵(TPAOH)促进Ni(200)的生长,而聚氧乙烯-聚氧丙烯-聚氧乙烯(P123)、聚乙烯吡咯烷酮(PVP)和十六烷基三甲基溴化铵(CTAB)抑制Ni(200)晶面的生长;Ni(200)的结晶程度对CH4的活化起到关键的作用,催化剂CB-LDO在高温下反应会发生晶型的转化, Ni(200)晶面由于反应过程中生成NiAl2O4尖晶石而得到缓慢释放,使催化剂的活性得以维持较高的水平。
关键词:
表面活性剂
,
共沉淀法
,
镍
,
镁铝氧化物
,
甲烷
,
二氧化碳
,
重整