The development of three-way catalysts with improved low temperature activity is essential for automotive catalysis. Here, we show that solution atomic layer deposition (SALD) of titania or zirconia promoters on alumina supports lowers the light-off temperatures of rhodium-based catalysts by 50–150 °C compared to a commercial benchmark three-way catalyst. X-ray diffraction, scanning transmission electron microscopy–electron energy loss spectroscopy, diffuse reflectance UV–visible spectroscopy and X-ray absorption near edge structure results indicate that titania incorporated by SALD at one monolayer loading is present primarily as atomically disperse 5-coordinate Ti⁴⁺ species. These species persist after exposure to steam and corrosive gases at temperatures up to 960 °C. Zirconia incorporated onto alumina by SALD is present as few-nanometre oxide particles and supports a three-way catalyst activity that is superior to that of Rh on either alumina or zirconia. Our results show that molecularly precise synthesis can lead to robust promotion of precious metal activity and provide a promising path towards reducing emissions from gasoline vehicles.

具有改善的低温活性的三效催化剂的开发对于汽车催化至关重要。在这里，我们表明，与商业基准三效催化剂相比，氧化铝载体上的二氧化钛或氧化锆促进剂的溶液原子层沉积（SALD）使铑基催化剂的起燃温度降低了50-150°C。X射线衍射，扫描透射电子显微镜–电子能量损失光谱，漫反射紫外可见光谱和X射线在边缘结构附近的吸收结果表明，SALD在单层载荷下结合的二氧化钛主要以原子分散的5坐标Ti的形式存在。⁴⁺物种。这些物质在暴露于高达960°C的蒸汽和腐蚀性气体后仍然存在。通过SALD掺入氧化铝中的氧化锆以极少的纳米氧化物颗粒形式存在，并具有三元催化活性，该活性优于Rh在氧化铝或氧化锆上的活性。我们的结果表明，分子精确的合成可以导致贵金属活性的强劲提高，并为减少汽油车辆的排放提供了一条有希望的途径。