The speciation and catalytic activity of ceria supported transition metal oxides synthesized via incipient wetness impregnation are highly dependent on synthesis parameters such as the choice of metal precursor and the concentration of defects such as oxygen vacancies in the support. Here, cobalt oxide domains were synthesized on cerium oxide nanorods and commercial nanopowder via incipient wetness impregnation of cobalt (II) nitrate hexahydrate, cobalt (II) acetate, cobalt (III) acetylacetonate, and disodium cobalt (II) ethylenediaminetetraacetic acid at surface densities below monolayer coverage. Their reactivity was tested in the catalytic reduction of NO by CO. The steady-state deNOx activity at 250 °C of the catalyst prepared with cobalt (III) acetylacetonate and ceria nanorods was nearly three times greater than that of the control catalyst. From X-ray absorption spectroscopy it was seen that as-deposited cobalt precursors on a nanorod support were more highly coordinated than were cobalt precursors on comparable commercial ceria nanoparticles, possibly indicating anchoring at defects on the nanorods. A relationship was found between catalyst activity and the cobalt oxidation state of the fully calcined catalysts that suggests that deNOx activity is separately dependent on the cobalt oxide distribution and the presence of defects in the support. Overall, here it is shown that the two critical synthesis parameters of ligand choice and defected supports combine additively to improve reactivity of the supported cobalt oxide.

通过初期湿润浸渍合成的二氧化铈负载的过渡金属氧化物的形态和催化活性高度依赖于合成参数，例如金属前体的选择和载体中缺陷的浓度，例如氧空位。在这里，通过初始湿法浸渍六水合硝酸钴（II），醋酸钴（II），乙酰丙酮钴（III）和乙二胺四乙酸二钠（乙二胺四乙酸）的初始润湿浸渍，在氧化铈纳米棒和商用纳米粉体上合成了氧化钴结构域。单层覆盖。在用CO催化还原NO的过程中测试了它们的反应性。乙酰丙酮钴（III）和二氧化铈纳米棒制备的催化剂在250°C的稳态脱硝活性几乎是对照催化剂的三倍。从X射线吸收光谱法可以看出，纳米棒载体上沉积的钴前体比可比的商用二氧化铈纳米颗粒上的钴前体具有更高的配位性，这可能表明锚定在纳米棒上的缺陷上。发现催化剂活性和完全煅烧的催化剂的钴氧化态之间的关系表明，脱NOx活性分别取决于氧化钴分布和载体中缺陷的存在。总的来说，这里显示了配体选择和缺陷载体的两个关键合成参数相加组合以提高载体氧化钴的反应性。