Progress and challenges of spinel materials for catalytic combustion of methane

Methane (CH₄) serves as both a valuable fuel and a crucial raw material for chemicals, while also playing a pivotal role in coal mine safety and various industries. CH₄, as the world's second-largest greenhouse gas, is considered the “holy grail” of catalytic reactions for its activation and conversion. Catalytic combustion (2C) technology offers a rapid and continuous mean to mitigate CH₄ emissions and enhance both global warming and air quality. Effective catalyst selection plays a crucial role in this process. Spinel metal oxides (SMO) are as promising candidates due to their adaptable structure, composition, phase, valence state, morphology and defects. This paper reviews the progress made in the past decade in synthesizing and applying SMO catalysts for catalytic combustion of CH₄ (CCM) and highlights advancements in the catalytic removal of various pollutants beyond CH₄, achieved through modifications to SMO catalysts over the past five years. Finally, the challenges associated with designing and preparing efficient SMO catalysts for CH₄ removal and the future theoretical and applied research of SMO catalysts in CH₄ catalytic purification is prospected. This provides systematic guidance for the design and preparation of efficient spinel catalysts for catalytic removal of atmospheric pollutants.