过渡金属掺杂铈-锆固溶体催化剂制备及其评价

Preparation and activity evaluation of transition metal doped Ce-Zr solid solutions

选取过渡金属Cu、Co、Ni和Fe对Ce-Zr固溶体(CZO)进行掺杂改性,采用CO催化氧化为探针反应对其进行活性评价,考察过渡金属种类、掺杂量和掺杂方式对催化剂活性的影响。结果表明,对于过渡金属掺杂Ce-Zr固溶体,低温还原峰温度值越低,表面氧反应活性越高,催化剂活性越大,Cu掺杂的催化剂活性最高。共沉淀法与浸渍法制备Cu-CZO相比,Cu在共沉淀法制备的Cu-CZO中分散得更好,活性更高。Cu掺杂量占金属总物质的量30%时,有活性较小的单相CuO生成。采用共沉淀法制备,Cu掺杂量占金属总物质的量10%时,催化剂活性最高,T_(50)和T_(90)分别比CZO降低了294℃和378℃。

Abstract： M-Ce-Zr-O solid solutions （ M = Cu, Co, Ni, Fe ） （ M-CZO ） were prepared by copreeipitation and impregnation methods, and their activity was evaluated using CO catalytic oxidation as the probe reaction. The effects of metal types,doping amount and doping methods on the activity of the catalysts were investigated. The results showed that the lower the reduction peak temperature of M-CZO catalysts at low temperature was,the higher the activity of surface oxygen and the catalysts were ;the activity of Cu-CZO catalyst was the highest among M-CZO. Cu-CZO prepared by coprecipitation method had higher activity than that prepared by impregnation method due to Cu well-dispersion. CuO phase with lower activity was formed in CZO when Cu doping amount reached 30%. Cu-CZO prepared by coprecipitation method exhibited best catalytic activity when Cu doping amount was 10%. Compared with CZO, T50 and T90 of Cu-CZO lowered 294 ℃ and 378℃C, respectively.