Bimetallic Au–Pd nanoparticles supported on different ceria and titania nanostructures have been prepared by sol-immobilisation, and evaluated in the solvent-less selective oxidation of benzyl alcohol. The catalysts were characterised by TEM, STEM, XRD, XPS, ICP-AES, and nitrogen adsorption–desorption measurements. The activity of the catalysts was found to be strongly related to the morphology, structure and physiochemical properties of the supports. Au–Pd/ceria nanorods exhibited remarkably high catalytic activity (TOF > 35 900 h⁻¹), and was found to be considerably more active than Au–Pd/titanate nanotubes, and Au–Pd catalysts supported on conventional ceria and titania nanopowders. The outstanding catalytic performance of Au–Pd/ceria nanorods is attributed to the unique surface chemistry of ceria nanorods, and the ability of catalyst preparation method (i.e. sol-immobilisation) to control the metal particle size and the bimetallic alloy formation. The presence of surface defects and high concentration of oxygen vacancies and Ce³⁺ in ceria nanorods is likely responsible for the stabilisation of Au–Pd NPs during sol-immobilisation, which led to a very small mean particle size (2.1 nm) corresponding to a dispersion of approximately 52%, and a high surface metal concentration.

中文翻译：

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固定在纳米结构二氧化铈和二氧化钛上的Au-Pd NPs：载体形态对选择性氧化催化活性的影响†

负载在二氧化铈和二氧化钛纳米结构上的双金属Au-Pd纳米颗粒已经通过溶胶固定法制备，并在无溶剂的苄醇选择性氧化中进行了评估。通过TEM，STEM，XRD，XPS，ICP-AES和氮吸附-解吸测量对催化剂进行了表征。发现催化剂的活性与载体的形态，结构和物理化学性质密切相关。Au-Pd /二氧化铈纳米棒表现出极高的催化活性（TOF> 35 900 h ^-1），并被发现比Au-Pd /钛酸酯纳米管和在传统的二氧化铈和二氧化钛纳米粉体上负载的Au-Pd催化剂具有更高的活性。Au-Pd /二氧化铈纳米棒的出色催化性能归因于二氧化铈纳米棒的独特表面化学，以及催化剂制备方法（即溶胶固定）控制金属粒度和双金属合金形成的能力。二氧化铈纳米棒中表面缺陷的存在以及氧空位和Ce ^3+的高浓度可能是溶胶固定化过程中Au-Pd NPs稳定的原因，这导致非常小的平均粒径（2.1 nm）对应于a分散度约为52％，并且表面金属浓度高。