Ni对Cu/ZnO基甲醇裂解催化剂的促进机制

Mechanism of Cu/ZnO Based Catalysis for Methanol Decomposition Promoted by Nickel

通过XRD ,BET ,In situXPS等表征技术对Cu/ZnO基甲醇裂解制氢催化剂进行了详细的研究 .XRD结果表明 ,Cu Zn合金的生成是Cu/ZnO基催化剂在反应初期快速失活的主要原因 ;XRD ,BET和N2 O滴定实验结果表明 ,Ni助剂可能是通过提高Cu0 活性物种的分散度并维持Cu0 活性物种在催化反应过程中的稳定性而使Cu/Zn/Ni催化剂的活性及稳定性大幅度提高 .In situXPS结果表明 ,Ni助剂的加入可以诱导Cu/Zn/Ni催化剂表面在甲醇裂解反应过程中出现Cu+ ,从而由Cu0 /Cu+ 共同构成催化剂的活性中心 ,并最终导致Cu/Zn/Ni催化剂的高活性 .

XRD, BET and In-situ XPS techniques were used to study the performance of Cu/ZnO based catalysts for methanol decomposition. XRD studies indicated that the formation of Cu-Zn alloys was the major reason for the quickly deactivation of Cu/Zn catalyst for methanol decomposition at the initial stage of the reaction. XRD, BET and N2O titration results confirmed that nickel additive could increase the dispersity of active Cu-0 species during the catalytic process and maintain the stability during the reaction. In-situ XPS studies confirmed that the active center in Cu/Zn/Ni catalyst was Cu-0 and/or Cu+ species, in which Cu+ was formed during the reaction.