利用俄歇电子能谱(AES)和程序升温脱附谱(TDS)研究了NO2在Ag/Pt(110)双金属表面的吸附和分解.室温下NO2在Ag/Pt(110)双金属表面发生解离吸附，生成NO(ads)和O(ads)表面吸附物种.在升温过程中NO(ads)物种发生脱附或者进一步分解.500 K时NO2在Ag/Pt(110)双金属表面发生解离吸附生成O(ads)表面吸附物种. Pt向Ag传递电子，从而削弱Pt-O键的强度，降低O(ads)从Pt表面的并合脱附温度.发现能够形成具有稳定组成的Ag/Pt(110)合金结构，其表现出与Pt(110)-(1×2)相似的解离吸附NO2能力，但与O(ads)的结合明显弱于Pt(110)-(1×2).该AgPt(110)合金结构是可能的低温催化直接分解氮氧化物活性结构.%The adsorption and decomposition of NO2 on Ag/Pt(110) bimetal ic surfaces have been investigated by Auger electron spectroscopy (AES) and thermal desorption spectroscopy (TDS). At room temperature, NO2 undergoes dissociative chemisorption on Ag/Pt(110) bimetal ic surfaces, forming chemisorbed NO(ads) and O(ads). Upon heating, NO(ads) undergoes both desorption from the surface and further decomposition. At 500 K, NO2 chemisorbs dissociatively on Ag/Pt(110) bimetal ic surfaces, forming O(ads). Electron transfer occurs from Pt to Ag, therefore, the presence of Ag on Pt(110) surface weakens the binding energy of O(ads) with the surface and decreases the temperature required for the recombinative desorption of O(ads) from the surface. We observed the formation of a Ag/Pt(110) al oy structure that exhibits catalytic activity towards NO2 decomposition similar to that of Pt(110)-(1×2) but with a binding energy towards O(ads) much lower than that of Pt(110)-(1×2). Such a Ag/Pt(110) al oy structure may be active in catalyzing the direct decomposition of NOx at relatively low temperatures.
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