摘要
不同温度下对Pd膜表面进行了氧气毒化,并将毒化后的Pd膜在常温下与氢气进行反应,采用XPS、SEM、XRD等对反应前后Pd膜表面状态进行了表征与分析,研究了O2的毒化作用与吸氢反应对Pd膜表面形貌与化学成分的影响。结果表明:当毒化温度低于240℃时,氧原子在Pd膜表面的吸附量随毒化温度升高而增加,但无明显PdO生成;当毒化温度高于240℃时,在Pd膜表面生成了PdO并伴有微孔出现,随着毒化温度升高,PdO含量、微孔数量、微孔体积逐渐增加。在390℃毒化1h后,Pd膜表面完全形成PdO;所有试样在室温下与氢气反应1h后吸附态氧原子与PdO完全消失。Pd膜表面化学成分被完全还原成反应前状态,而多孔形貌得到一定的保留,240℃及以上温度毒化后的Pd膜与氢气反应后产生明显塑性变形。
The oxidation of palladium membrane at different temperatures and the hydrogenization of the oxidized membrane at room temperature were carried out in a silica tubular furnace. The variation of surface phase was observed and analyzed by XPS, SEM and XRD. The effects of O2 poison and hydrogenization on the surface morphology and composition of the Pd membrane were investigated. The results show that when the oxidation temperature is below 240 oC, the adsorptive capacity of O on the Pd surface is increased with the temperature rising but there is no obvious PdO. However, PdO together with micropores could be detected apparently at the oxidation temperature above 240 oC, and the mass ratio of PdO and the amount and dimension of the micropores are increased by further increasing the temperature. The Pd surface turns into PdO completely for the Pd membrane oxidized at 390 oC for 1 h. After hydrogenization, all of the PdO and free O on the Pd surface vanish; the surface phases of Pd membrane are reduced fully to the state before reaction, but the multiaperture surface is reserved. At 240 oC and the higher temperature, the oxidized Pd membrane can react with hydrogen, resulting in obvious plastic deformation.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2011年第4期697-700,共4页
Rare Metal Materials and Engineering
基金
表面物理与化学国家重点实验室开放基金(SPC200701)
关键词
PD膜
毒化
氧气
氢气
表面
Pd membrane
poison
oxygen
hydrogen
surface
