Yang Ke, Li Chenqi, Zhu Qinghan, Wang Haiwang, Qi Jian
Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China.
State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
Nanomaterials (Basel). 2025 Mar 31;15(7):524. doi: 10.3390/nano15070524.
Methane is the second most prevalent greenhouse gas after carbon dioxide in global climate change, and catalytic oxidation technology is a very effective way to eliminate methane. However, the high reaction temperature of methane catalytic oxidation is an urgent problem that needs to be solved. In this work, a series of MnCoO catalysts were prepared using carbon spheres as templates, combined with metal ion adsorption and calcination processes. Excitingly, the catalytic oxidation activity of MnCoO spherical catalyst with irregular nanoparticles on the surface for lean methane (T = 395 °C) is higher than that of pure phase CoO (T = 538 °C) and MoO (T = 581 °C) spherical catalysts and even surpasses most precious metal catalysts. The main reasons are as follows: (1) The spherical core with irregular nanoparticle morphology significantly increases the specific surface area, creating abundant active sites; (2) through the optimized distribution of oxygen vacancies, rapid oxygen migration through this structure can quickly enter the catalytic zone; (3) the hierarchical wall structure expands the interface and provides spatial accommodation for the catalytic process. Meanwhile, the structure of the ball wall further expands the reaction interface, providing sufficient space for the occurrence of reactions. Rich and highly active oxygen vacancies are evenly distributed on the surface and inside of the ball. The extraordinary performance of low-temperature methane combustion catalysts has opened a promising new path, which is expected to inject strong impetus into the global energy transition and environmental protection.
甲烷是全球气候变化中仅次于二氧化碳的第二大温室气体，催化氧化技术是消除甲烷的一种非常有效的方法。然而，甲烷催化氧化反应温度高是一个亟待解决的问题。在这项工作中，以碳球为模板，结合金属离子吸附和煅烧过程制备了一系列MnCoO催化剂。令人兴奋的是，表面具有不规则纳米颗粒的MnCoO球形催化剂对贫甲烷的催化氧化活性（T = 395 °C）高于纯相CoO球形催化剂（T = 538 °C）和MoO球形催化剂（T = 581 °C），甚至超过了大多数贵金属催化剂。主要原因如下：（1）具有不规则纳米颗粒形态的球形核显著增加了比表面积，产生了丰富的活性位点；（2）通过优化氧空位分布，氧气通过这种结构的快速迁移可以迅速进入催化区；（3）分级壁结构扩展了界面，并为催化过程提供了空间容纳。同时，球壁结构进一步扩大了反应界面，为反应的发生提供了足够的空间。丰富且高活性的氧空位均匀分布在球的表面和内部。低温甲烷燃烧催化剂的优异性能开辟了一条前景广阔的新路径，有望为全球能源转型和环境保护注入强大动力。
