Supported noble metal catalysts have been widely utilized for HCHO catalytic oxidation. When the active components are fixed, the altering and regulation of the supports would have a huge effect on catalytic performance. Here, two types of Pd/γ-Al₂O₃ catalysts with different support size (micro-γ-Al₂O₃ and nano-γ-Al₂O₃, respectively) were fabricated and used for HCHO oxidation. Compared with the micro-sized counterpart, the Pd/nano-γ-Al₂O₃ catalyst exhibited much superior HCHO oxidation performance which could totally oxidize 160 ppm of HCHO into harmless CO₂ under a WHSV of 100,000 mL g_cat⁻¹ h⁻¹ at room temperature. Multiple characterizations including XRD, BET, TEM, CO chemisorption, FT-IR, O₂-TPD, XPS and in situ DRIFTS were implemented to study the effect of γ-Al₂O₃ support size on physicochemical properties of Pd/γ-Al₂O₃ catalysts and elucidate the structure-activity relationship. The results revealed that large specific surface area, rich surface OH groups as well as high curvature of nano-γ-Al₂O₃ not only facilitated HCHO adsorption, but also stabilized highly dispersed Pd species which then promoted the activation of oxygen and boosted formate species decomposition, and consequently leading to the enhanced HCHO oxidation performance of Pd/nano-γ-Al₂O₃. This work deepens the comprehension of support size-dependent activity of Pd/γ-Al₂O₃ catalysts for HCHO oxidation and provides an alternative method to prepare high-performance Pd catalysts for HCHO oxidation.

负载型贵金属催化剂已广泛用于HCHO催化氧化。当活性成分固定后，载体的改变和调节将对催化性能产生巨大影响。这里，两种类型的Pd /γ-Al系的_2种ö ₃催化剂与不同的支撑大小（微的γ-Al ₂ ö ₃和纳米的γ-Al ₂ ö ₃，分别地）被制造并用于HCHO氧化。与微小尺寸的配对中，Pd /纳米的γ-Al相比₂ ö ₃催化剂显示出更优异的HCHO氧化性能可能完全氧化为160ppm HCHO的成无害的CO ₂ 100000毫升g的WHSV下_猫室温下^-1  h ^-1。多个表征包括XRD，BET，TEM，CO化学吸附，FT-IR，O- ₂ -TPD，XPS和原位DRIFTS实施了学习的效果的γ-Al ₂ ö ₃上的Pd /γ-Al系的物理化学性质支持尺寸并阐明了₂ O ₃催化剂的构效关系。结果表明，比表面积大，表面富OH基团以及的高曲率纳米的γ-Al ₂ ö ₃不仅促进HCHO吸附，但也稳定高度分散的Pd物种，然后促进氧的活化和升压甲酸盐物种分解，并因此导致的Pd /纳米γ-Al的增强HCHO氧化性能₂ ö ₃。这项工作的深入的Pd /γ-Al系的支撑大小依赖性活性的理解_2个ø ₃催化剂HCHO氧化和提供了一种替代方法，以制备高性能的Pd催化剂HCHO氧化。