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

The NOx storage catalyst Pt/BaAl2O4–Al2O3 was prepared by a coprecipitation–impregnation method. For fresh sample, the barium mainly exists as the BaAl2O4 phase except for some BaCO3 phase. The BaAl2O4 phase is the primary NOx storage phase of the sample. EXAFS and TPD were used for investigating the mechanism of NOx storage. It is found that two kinds of Pt sites are likely to operate. Site 1 is responsible for NO chemisorption and site 2 for oxidizing NO to nitrates and nitrites. When NO adsorbs on the sample below 200℃, it mainly chemisorbs in the form of molecular states. Such adsorption results in an increase of the coordination magnitude of Pt–O, and a decrease of that of Pt–Pt and Pt–Cl. The coordination distance of Pt–Pt, Pt–Cl and Pt–O also increases. When the adsorption occurs above 200℃, NO can be easily oxidized by O2, and stored as nitrites or nitrates at the basic BaAl2O4. Site 2 is regenerated quickly. A high adsorption temperature is favorable for nitrate formation.

The complex oxide Ba–Fe–O catalysts were prepared by sol–gel method. The XRD, DTA, NO-TPD, XPS and NSC measurements were used to characterize the structures, NOx storage property and sulfur resistance ability. It is concluded that when coadsorption of NO and O2 at 400 C, the sample calcined at 750℃ possesses high NOx storage capacity and sulfur resistance. The perovskite type BaFeO3 and BaFeO3-x phases are the active centers in the catalyst for NOx storage.

A new NOx storage-reduction electrochemical catalyst has been prepared from a polycrystalline Pt film deposited on 8 mol% Y2O3- stabilized ZrO2 (YSZ) solid electrolyte. BaO has been added onto the Pt film by impregnation method. The NOx storage capacity of Pt-BaO/ YSZ system was investigated at 350℃ and 400℃ under lean conditions. Results have shown that the electrochemical catalyst was effective for NOx storage. When nitric oxides are fully stored, the catalyst potential is high and reaches its maximum. On the other hand, when a part of NO and also NO2 desorb to the gas phase, the catalyst potential remarkably drops and finally stabilizes when no more NOx storage occurs but only the reaction of NO oxidation into NO2. Furthermore, the investigation has clearly demonstrated that the catalyst potential variation versus temperature or chemical composition is an effective indicator for in situ following the NOx storage-reduction process, i.e. the storage as well as the regeneration phase. The catalyst potential variations during NOx storage process was explained in terms of oxygen coverage modifications on the Pt.