Toluene oxidation on three ceria catalysts, CeO₂, VO_x/CeO₂ and Au/CeO₂, was investigated by an operando Raman-online FTIR reactor cell. The reactive surface oxygen sites were preferred sites for vanadium and gold deposition. The deposited vanadium existed as V⁵⁺, while most of the gold was in Au⁺ state and roughly a third of ceria was in the reduced Ce³⁺ state. The Au/CeO₂ and CeO₂ catalysts (T₅₀^∗ = 260 and 290 °C) were more active and selective toward the complete oxidation of toluene than VO_x/CeO₂ catalyst (T₅₀^∗ = 370 °C), where T₅₀^∗ refers to the temperature for 50% of CO₂ yield. The η²-peroxide O_2 ads²⁻ was detected on Au/CeO₂ and CeO₂ catalysts, where toluene molecules preferentially adsorbed parallel to the surface via π-bonding. Au/CeO₂ gave complete combustion producing mainly CO₂. On the other hand, η¹-superoxide O_2 ads⁻ was found on VO_x/CeO₂ catalyst and the toluene molecule adsorbed via σ-bonding forming carbenium ions on the vanadia Brønsted acid sites. This catalyst produced significant amount of benzaldehyde as partial oxidation byproduct and CO (<25%). The nature of the active sites, configurational adsorption of toluene and the reactive oxygen species play important roles in the catalyst activity and selectivity leading to a large contrast in the catalytic behavior of the CeO₂, VO_x/CeO₂ and Au/CeO₂ catalysts.

通过操作拉曼在线FTIR反应器池研究了三氧化铈催化剂CeO ₂，VO _x / CeO ₂和Au / CeO ₂上的甲苯氧化。反应性表面氧位是钒和金沉积的优选位。沉积的钒以V ^5+的形式存在，而大多数金以Au ⁺态存在，大约三分之一的二氧化铈以还原的Ce ³⁺态存在。Au / CeO ₂和CeO ₂催化剂（T ₅₀ ^*  = 260和290°C）比VO _x / CeO ₂具有更高的活性和对甲苯的完全氧化的选择性催化剂（T ₅₀ ^＊  = 370°C），其中T ₅₀ ^＊表示50％CO ₂收率的温度。的η ² -peroxideÒ _2个 广告^2-对Au /负责检测₂和的CeO _2种催化剂，其中甲苯分子优先平行吸附到表面通过π键合。Au / CeO ₂完全燃烧，主要产生CO ₂。在另一方面，η ¹ -superoxideÒ _2个广告^-已于VO发现_X /的CeO ₂催化剂和甲苯分子吸附经由钒在布朗斯台德酸位上的σ键形成碳正离子。该催化剂产生大量苯甲醛作为部分氧化副产物和CO（<25％）。活性位点的性质，甲苯的构型吸附和活性氧种类在催化剂活性和选择性中起重要作用，从而导致CeO ₂，VO _x / CeO ₂和Au / CeO ₂催化剂的催化行为形成很大的反差。。