Several nanosized catalysts Co3O4–CeO2 with varying compositions were synthesized by a surfactant-template method and further promoted by a small amount of Pd (0.5 wt%). These catalysts exhibit uniform mesoporous structure and high surface area (>100 m2 g−1). The Co3O4 crystallites in these catalysts are encapsulated by nanosized CeO2 with only a small fraction of Co ions exposing on the surface and strongly inter- acting with CeO2. Such structure maximizes the interaction between Co3O4 and CeO2 in three dimensions, resulting in unique redox properties. The introduction of Pd prominently enhances both the reduction and oxidation performance of the catalysts, due to hydrogen or oxygen spillover. These catalysts prepared by surfactant-template method exhibit excellent oxidation performance, especially the ones promoted with Pd, which show markedly enhanced CO oxidation activity even at room temperature. Based upon the results of structural properties, redox behaviors and in situ DRIFTS study, two different reaction pathways over Co3O4–CeO2 and Pd/Co3O4–CeO2 are proposed.

The combustion of light hydrocarbons finds an important application in volatile organic compounds (VOCs) abatement. Catalytic combustion is interesting in this domain, because it may be carried out at relatively low temperatures and under large air excess. For this purpose, precious metal-based catalysts are very performing, but the quest for a lower-cost alternative solution is necessary. In this field, conducting mixed oxides such as perovskites are good candidates, especially when they are electrochemically promoted. The present work shows that electrochemical promotion of catalytic activity (NEMCA effect) in propene total combustion can be carried out with La0.8Sr0.2Co0.8Fe0.2O3, an electron-conducting perovskite-type oxide, deposited on YSZ.

Electrochemical catalysts were used for environmental applications, such as the clean production of energy from propane and propene combustion, the elimination of VOC’s like propene and the NOx abatement All the selected electrochemical catalysts were composed of a Pt film deposited on YSZ, NASICON or CGO. It was found that all these chemical reactions can be electropromoted. Moreover, the reaction rates can be in-situ tuned by applying a polarisation. Furthermore, the selectivity of Pt-based electrochemical catalysts can be modified in order to avoid the formation of pollutant. Finally, EPOC can improve the lifetime of a catalyst by inhibiting its poisoning by carbonaceous species.

采用共沉淀-浸渍法制备了Pt/Co-Ba-Al-O催化剂，用X射线衍射、X射线吸收近边结构和扩展X射线吸收精细结构等手段表征了催化剂的微观结构，并在连续流动微型反应器上测定了催化剂对NOx的储存性能。载体经过800℃焙烧后，Co物种主要以四面体配位的铝酸钴相存在。在富氧条件下，高分散的小颗粒铝酸钴相促进了NO向NO2的转化，大大改善了催化剂对NOx的储存性能。铂物种则以小的金属原子簇形式存在，分散度很高。钴助剂的添加改善了氧化铝相的分散度，抑制了金属铂原子簇与载体的相互作用，使铂在催化剂表面分散得更均匀，从而有利于NOx的储存