为了考察杂质气体对钯吸氢速率的影响, 测定了钯粉末暴露在CO, O2, H2O中后25 ℃下的吸氢速率. 与洁净钯吸氢速率相比, CO预覆盖引起钯吸氢速率降低最为显著, H2O次之;少量O2预覆盖却能引起钯吸氢速率显著增加. 引起吸氢速率变化的微观机制主要是受氢原子在氢化物层的扩散或钯表面解离氢分子的化学吸附;O2预覆盖可使Pd表面形成多孔结构而增加了氢分子的解离位, 从而增加吸氢速率;CO预覆盖后却占领了钯表面的氢分子解离位而减小了吸氢速率. 250 ℃下的O2预处理是CO毒化钯活化的有效方法.
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