Recent advances in active component regulation, catalytic oxidation mechanisms, and poisoning resistance of diesel oxidation catalysts ( DOCs )

Abstract Diesel oxidation catalysts (DOCs) are a crucial component of diesel engine exhaust aftertreatment systems, primarily employed for the oxidation removal of carbon monoxide (CO) and hydrocarbons (HC), as well as promoting the conversion of soluble organic fractions (SOF) in particulate matter (PM). Meanwhile, DOCs provide essential reaction conditions for subsequent selective catalytic reduction (SCR) and diesel particulate filter (DPF) systems. With increasingly stringent emission regulations, DOC catalysts are facing higher requirements in terms of low‐temperature catalytic activity, durability, and poisoning resistance. This review systematically summarizes the preparation methods and structural regulation strategies of DOC catalysts, and discusses the applications of characterization techniques in active site identification and reaction mechanism investigation. The effects of noble metal species, support properties, reaction temperature, and gas composition on catalytic oxidation performance are comprehensively analyzed. Furthermore, typical deactivation mechanisms, including sulphur poisoning, thermal aging, and carbon deposition, are summarized, and recent advances in improving poisoning resistance and stability through promoter modification, structural optimization, and surface engineering are evaluated. Finally, based on the current research status, the remaining challenges of DOC catalysts in low‐temperature high‐efficiency catalysis, adaptability under complex operating conditions, and multifunctional integration are discussed, along with future development perspectives.