Although oxygen vacancies (OVs) commonly act as adsorption/active sites in catalytic oxidation of formaldehyde (HCHO), thereby strongly influencing catalyst activity, their control and translation into scale-up products for practical application remain challenging. Herein, δ-MnO_x/activated carbon was synthesized via in situ reduction coupled with ammonia modification, and the developed method was found to allow easy OV control for large-scale production. OV concentration was effectively regulated through adjustment of Mn³⁺ content, and OV roles in the catalytic reaction were probed by several techniques. The optimized catalyst featured superior HCHO removal efficiency and CO₂ selectivity at room temperature, mainly due to oxygen activation by abundant OVs to form reactive oxygen species. The intermediates and pathways of HCHO removal were investigated. Thus, this work provides insights into the enhancement of active site exposure through OV control for a single bulk catalyst and demonstrates its applicability for efficient and commercially viable room-temperature oxidation of HCHO.

尽管氧空位（OVs）通常在甲醛（HCHO）的催化氧化中充当吸附/活性位点，从而强烈影响催化剂的活性，但其控制和转化为实际应用的规模化产品仍然具有挑战性。此处，δ-MnO的_X /活性炭经由耦合用氨改性原位还原合成，并且发现所提出的方法，以允许大规模生产容易OV控制。通过调节Mn ³⁺含量可以有效地调节OV的浓度，并通过多种技术探索OV在催化反应中的作用。优化的催化剂具有出色的HCHO去除效率和CO ₂在室温下具有选择性，这主要归因于大量OV活化氧以形成活性氧。研究了去除HCHO的中间体和途径。因此，这项工作为通过单一单体催化剂的OV控制提高活性位点暴露提供了见识，并证明了其可用于HCHO的有效和商业可行的室温氧化。