Chemical reactivity and thermal stability of nanometric alkali metal hydrides
Chemical reactivity and thermal stability of nanometric alkali metal hydrides
复制标题
纳米碱金属氢化物的化学反应性和热稳定性
DOI：
10.1007/s11051-005-9064-3
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发表时间：
2006-12-01
影响因子：
2.5
通讯作者：
Xu, Jie
中科院分区：
文献类型：
--
作者：
Fan, Yinheng;Li, Weina;Xu, Jie
通过三种试验反应，比较了纳米钠颗粒与工业钠颗粒的化学反应活性。当这些颗粒用作化学试剂时，与它们的商业对应物相比，这些纳米颗粒的大比表面积是它们具有极高反应性的主要因素。然而，当纳米nah与Cp2TiCl2作为助催化剂时，具有高表面能的活化表面似乎是其高催化活性的主要因素。研究了氢化锂、氢化钠和氢化钾纳米颗粒的热稳定性和化学反应性。热处理前锂、钠和钾氢化物的平均粒径分别为22、23和19 nm。采用烯烃的催化加氢反应和氯苯的加氢脱氯反应作为实验反应，考察了不同温度下纳米颗粒的化学反应活性。随着热处理温度的升高，纳米颗粒逐渐长大，BET比表面积同时减小。在适当温度下进行热处理，纳米氢化物表面明显活化。
The chemical reactivities of nano-NaH particles were compared with those of the commercial ones in three test reactions. Large specific surface areas of these nanoparticles are the main factor for their extremely high reactivity in comparison with their commercial counterpart when these particles are used as a chemical reagent. However, when nano-NaH is used as a cocatalyst with Cp2TiCl2, activated surface with high surface energy seems to be the main factor for its high catalytic activity. The thermal stability and chemical reactivity of nanoparticles of lithium hydride, sodium hydride and potassium hydride have been studied. The average particle sizes of lithium, sodium and potassium hydrides before heat treatment are 22, 23 and 19 nm, respectively. Catalytic hydrogenation of olefins and hydrodechlorination of chlorobenzene were employed as test reactions for the chemical reactivities of these nanoparticles treated at different temperatures. The nanoparticles grow with the increase of heat treatment temperature, and the BET specific surface areas decrease simultaneously. An activation of the nanometric hydride surface is evident via the heat treatment under suitable temperatures.