So far, it is still a controversial issue which status of gold species is a better active site for catalyzing CO oxidation. Herein, the influence of the different atmospheres pretreatment (oxidative and reductive) on gold state of Au/La-CeO_x (1 wt% gold loading) catalyst during CO oxidation was studied. The changes of Au species were monitored by combined in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) and X-ray photoelectron spectroscopy (XPS). For the sample pretreated with oxidative atmosphere, the data show that the initial Au³⁺ is transformed to Au^δ+ (0 < δ < 1) during CO oxidation, which is a key step to lead to higher reactivity. For the sample after reductive atmosphere pretreatment, Au^δ+ is mixed with a small amount of Au⁰ which can be converted to Au^δ+ with the increase of temperature in reaction. Meanwhile, the sample always maintains high activity during the reaction. Therefore, the Au^δ+ obtained by reductive pretreatment is more active than the Au³⁺ obtained by oxidative treatment in catalyzing CO oxidation.

迄今为止，金的状态是否是催化CO氧化的更好的活性位点仍然是一个有争议的问题。在此，研究了在CO氧化过程中，不同气氛预处理（氧化性和还原性）对Au / La-CeO _x（金含量为1 wt％）催化剂的金态的影响。通过原位漫反射红外傅里叶变换光谱法（原位DRIFTS）和X射线光电子能谱法（XPS）监测金的变化。对于具有氧化性气氛预处理的样本，所述数据显示，最初的Au ³⁺被变换成的Au ^{δ +}（0 <  δ <1）在CO氧化过程中，这是导致更高反应性的关键步骤。为还原性气氛的预处理后的样品，AU ^{δ +}与Au的混入少量⁰，其可以被转化成的Au ^{δ +}随温度的反应的增加。同时，样品在反应过程中始终保持高活性。因此，在Au ^{δ +}通过还原预处理获得比金更积极³⁺通过在催化CO氧化的氧化处理而得到的。