A novel simple and easy impregnation method for preparation of small gold (Au) nanoparticle (NP) catalysts (<3 nm) deposited on various supports including silica, which is difficult to be applied for conventional methods, has been developed. Chloride-free and water-soluble precursor, Au complexes coordinated with β-alanine, were successful for the preparing Au NPs, which exhibited an average diameter less than 3 nm. Thermal behavior of the Au complex was investigated by TG-DTA and in situ XAFS. XAFS analyses and DFT calculations revealed a molecular structure of the Au complex to be square-planar coordination structure and mononuclear complex of Au³⁺. Lower decomposition and reduction temperature of the chloride-free Au complex prevented Au atoms from aggregating and from following growth of Au particles. The prepared Au/SiO₂ showed high selectivity for hydrogenation of 1-nitro-4-vinylbenzene into 1-ethyl-4-nitorobenzene and good performance for removal of unpalatable aroma by means of adsorption of polysulfide molecules.

已开发出一种新颖，简单的浸渍方法，用于制备沉积在包括二氧化硅在内的各种载体上的小金（Au）纳米颗粒（NP）催化剂（<3 nm），该方法难以应用于常规方法。不含氯化物和水溶性的前体，与β-丙氨酸配位的Au配合物，成功制备了平均直径小于3 nm的Au NP。通过TG-DTA和原位XAFS研究了Au络合物的热行为。XAFS分析和DFT计算表明Au配合物的分子结构为方平面配位结构和Au ^3+的单核配合物。不含氯化物的Au络合物的较低分解和还原温度可防止Au原子聚集以及随后Au颗粒的生长。制备的Au / SiO ₂对1-硝基-4-乙烯基苯加氢成1-乙基-4-硝基苯具有较高的选择性，并具有通过吸附多硫化物分子去除难闻的香气的良好性能。