摘要
采用共沉淀法合成了Ｎｉ／Ｆｅ摩尔比为１、２、３、６和１０的ＮｉＦｅ水滑石。热重差热结果显示ＮｉＦｅ水滑石的分解有二个过程，分别对应于２００℃和３００℃的吸热峰。经４００℃焙烧后，ＮｉＦｅ水滑石转变为具有较高表面积的ＮｉＦｅＯ混合氧化物（约１００ｍ２／ｇ），其ＸＲＤ结果仅显示ＮｉＯ的衍射峰；经８００℃焙烧后，ＮｉＦｅＯ仍有１５ｍ２／ｇ左右的表面积。穆斯堡尔谱测定表明ＮｉＦｅＯ混合氧化物较Ｆｅ２Ｏ３易还原。
A series of NiFe hydrotalcites with Ni/Fe molar ratios of 1,2,3,6 and 10 was synthesized by coprecipitation. TG DTA results showed that the decomposition of the hydrotalcite samples proceeded in two stages, corresponding to the two endothermic peaks around 200℃ and 300℃, respectively. After calcination at 400℃, the hydrotalcites were transformed into NiFeO mixed oxides with high surface areas around 200 m 2/g. The mixed oxides thus formed exhibited the same XRD patterns as that of NiO. The mixed oxides still possess the surface area of about 15 m 2/g even after calcination at 800℃, higher than that of NiFeO synthesized by the conventional method of coprecipitation. XRD and Moessbauer spectroscopy revealed that Fe 3+ cations highly distributed in the lattice of the mixed oxides. In situ M o·· essbauer spectroscopy showed that the mixed oxides can be reduced to NiFe alloy at 300℃ in H 2.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
1997年第2期159-163,共5页
Chinese Journal of Inorganic Chemistry
基金
国家教委跨世纪优秀人才基金
关键词
镍铁水滑石
混合氧化物
催化剂
热分析
NiFe hydrotalcite\ \ \ NiFeO mixed oxide\ \ \ structure characterization thermal analysis\ \ \ reducibility
