We report the catalytic performance of Au–Pd nanoparticles prepared via a sol immobilisation technique for the catalytic hydrogenation of cinnamaldehyde under mild reaction conditions. We synthesised a series of bimetallic Au–Pd colloidal supported nanoparticles with different Au : Pd molar ratios and optimized the experimental parameters to achieve the best catalyst performance. The optimum catalytic activity for the hydrogenation of cinnamaldehyde was observed for Au₅₀Pd₅₀/TiO₂ (with a Au : Pd molar ratio of 1 : 1), while the monometallic Pd/TiO₂ was the most selective towards hydrocinnamaldehyde. The catalysts have been structurally characterised and FTIR analysis showed that the presence of adsorbed carbonyl surface species in used catalyst materials is coupled with Pd leaching, which is the main reason for catalyst deactivation. The effect of calcination on the most active Au–Pd/TiO₂ was studied in the range 110–400 °C and a direct correlation between the rise in calcination temperature and catalyst stability and selectivity was observed. These results emphasise the importance of tuning the Au–Pd molar ratio and understanding the metal–support interaction of catalysts synthesised for hydrogenation reactions, such as cinnamaldehyde hydrogenation.

中文翻译：

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使用通过溶胶固定法制备的Au-Pd催化剂氢化肉桂醛†

我们报告了通过溶胶固定化技术在温和的反应条件下对肉桂醛进行催化氢化制备的Au-Pd纳米颗粒的催化性能。我们合成了一系列具有不同Au：Pd摩尔比的双金属Au-Pd胶体负载纳米颗粒，并优化了实验参数以实现最佳催化剂性能。对于Au ₅₀ Pd ₅₀ / TiO ₂（Au：Pd摩尔比为1：1），观察到肉桂醛加氢的最佳催化活性，而单金属Pd / TiO ₂对氢肉桂醛的选择性最高。对该催化剂进行了结构表征，FTIR分析表明，所用催化剂材料中吸附的羰基表面物质的存在与Pd浸出有关，这是催化剂失活的主要原因。研究了在110–400°C范围内煅烧对最具活性的Au-Pd / TiO ₂的影响，并观察到煅烧温度的升高与催化剂稳定性和选择性之间的直接相关性。这些结果强调了调整Au-Pd摩尔比和理解用于氢化反应（例如肉桂醛氢化）的合成催化剂的金属-载体相互作用的重要性。