Well-dispersed and uniformly sized 5–84 nm Mo oxide and CoMo oxide nanoparticles were synthesized by varying the Mo and Co precursor concentrations. The water-gas shift (WGS) activity of sulfided Mo-based catalysts was found to increase with particle size and in the presence of Co. In particular, 84-nm CoMo-S nanoparticles exhibited 15 times higher effective CO consumption rate and 2.3 times higher turnover frequency (TOF) as compared to 5- nm Mo-S nanoparticles. The observed trends in size-dependent catalytic behavior correlated with the higher density of the proposed active sites present on larger (Co)Mo-S nanoparticles probed by CO chemisorption.

通过改变Mo和Co的前驱体浓度，可以合成分散均匀且尺寸均匀的5-84 nm的Mo氧化物和CoMo氧化物纳米颗粒。发现硫化的Mo基催化剂的水煤气变换（WGS）活性随着粒径的增加和在Co的存在下增加。特别是，84 nm CoMo-S纳米颗粒的有效CO消耗率高15倍，而CO消耗率高2.3倍与5 nm Mo-S纳米颗粒相比，具有更高的周转频率（TOF）。观察到的与尺寸有关的催化行为的趋势与通过CO化学吸附探测到的较大（Co）Mo-S纳米颗粒上提议的活性位点的较高密度相关。