Highly dispersed precious metals are critical to many important catalytic reactions and strongly affect the activity of catalysts. In this work, a simple method to stabilize noble metals on Pd/TiO₂ catalyst by constructing Ti³⁺ defects on the surface of TiO₂ supports. The TiO₂ samples with different contents of Ti³⁺ defects were used to prepare a series of Pd/TiO₂ catalysts, which were tested in formaldehyde (HCHO) oxidation. Multiple characterization results illustrated that the Ti³⁺ defects on TiO₂ produced by hydrogen pretreatment during high temperature reduction (HTR), favored the stabilization of Pd particles through the strong metal-support interaction (SMSI). The increasing Pd dispersion induced more oxygen vacancies on the surfaces of Pd/TiO₂ catalysts, because of hydrogen spillover, and further increased the electron density of Pd species. The activation of water and oxygen was also promoted to form more surface oxygen species. Therefore, the more surface defects existing, the better performance of Pd/TiO₂ catalysts displayed for HCHO oxidation.

高度分散的贵金属对于许多重要的催化反应至关重要，并严重影响催化剂的活性。在这项工作中，一种通过在TiO ₂载体表面上构建Ti ³⁺缺陷来稳定Pd / TiO ₂催化剂上的贵金属的简单方法。使用具有不同含量的Ti ³⁺缺陷的TiO ₂样品制备了一系列Pd / TiO ₂催化剂，并在甲醛（HCHO）氧化中进行了测试。多种表征结果表明，TiO ₂上的Ti ³⁺缺陷在高温还原（HTR）期间通过氢气预处理产生的金属，有助于通过强金属-载体相互作用（SMSI）稳定Pd颗粒。由于氢的溢出，Pd分散度的增加引起Pd / TiO ₂催化剂表面更多的氧空位，并进一步增加了Pd的电子密度。水和氧气的活化也被促进以形成更多的表面氧种类。因此，存在的表面缺陷越多，用于HCHO氧化的Pd / TiO ₂催化剂的性能越好。