A simple strategy was used to prepare Au/TiO₂ catalyst at room temperature. Au nanoparticles were initially prepared in solution using HAuCl₄.3H₂O as Au precursor, sodium citrate as stabilizing agent and sodium borohydride as reducing agent. The preformed Au nanoparticles were further supported on TiO₂ and the resulting solid material was characterized by Energy-dispersive X-ray spectroscopy, X-ray diffraction and Transmission Electron Microscopy and tested for the preferential oxidation of carbon monoxide in hydrogen-rich stream (CO-PROX reaction). The obtained Au/TiO₂ catalyst consisted of Au nanoparticles with an average size of ~ 4 nm and showed excellent catalytic performance in the 20-50 °C low-temperature range. In particular, at 40 °C a CO conversion of 99.5% and CO₂ selectivity of 45% were obtained using an O₂/CO ratio of 2 (1 vol% CO, λ = 4) and 97 vol% H₂ in the feed gas stream (GHSV = 15,000 mL g_cat⁻¹ h⁻¹).

一种简单的策略用于在室温下制备Au / TiO ₂催化剂。首先使用HAuCl ₄ .3H ₂ O作为Au前体，柠檬酸钠作为稳定剂和硼氢化钠作为还原剂在溶液中制备Au纳米颗粒。将预先形成的Au纳米颗粒进一步负载在TiO _2上，并通过能量色散X射线光谱，X射线衍射和透射电子显微镜对所得固体材料进行表征，并测试富氢流（CO）中一氧化碳的优先氧化-PROX反应）。所得的Au / TiO ₂催化剂由平均粒径约为4 nm的Au纳米颗粒组成，在20-50°C的低温范围内显示出优异的催化性能。尤其是，在40°C下，进料中的O ₂ / CO比为2（1％（体积），λ= 4）和97％（体积）的H _2时，CO转化率为99.5％，CO ₂选择性为45％。气流（GHSV = 15,000 mL g _cat ^-1  h ^-1）。