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Increasing the contact efficiency and improving the intrinsic activity are two effective strategies to obtain efficient catalysts for soot combustion. Herein, the electrospinning method is used to synthesize fiber-like Ce–Mn oxide with a strong synergistic effect. The slow combustion of PVP in precursors and highly soluble manganese acetate in spinning solution facilitates the formation of fibrous Ce–Mn oxides. The fluid simulation clearly indicates that the slender and uniform fibers provide more interwoven macropores to capture soot particles than the cubes and spheres do. Accordingly, electrospun Ce–Mn oxide exhibits better catalytic activity than reference catalysts, including Ce–Mn oxides by co-precipitation and sol-gel methods. The characterizations suggest that Mn3+ substitution into fluorite-type CeO 2 enhances the reducibility through the acceleration of Mn–Ce electron transfer, improves the lattice oxygen mobility by weakening the Ce–O bonds, and induces oxygen vacancies for the activation of O 2. The theoretical calculation reveals that the release of lattice oxygen becomes easy because of a low formation energy of oxygen vacancy, while the high reduction potential is beneficial for the activation of O 2 on Ce3+-Ov (oxygen vacancies). Due to above Ce–Mn synergy, the CeMnO x -ES shows more active oxygen species and higher oxygen storage capacity than CeO 2 -ES and MnO x -ES. The theoretical calculation and experimental results suggest that the adsorbed O 2 is more active than lattice oxygen and the catalytic oxidation mainly follows the Langmuir-Hinshelwood mechanism. This study indicates that electrospinning is a novel method to obtain efficient Ce–Mn oxide. [Display omitted] • The fibrous oxides provide interwoven macropores to capture soot particles. • Mn substitution improves the intrinsic activity by the Ce–Mn Synergy. • The adsorbed O 2 prefers to be activated on oxygen vacancies around Ce3+. • The catalytic oxidation of soot mainly follows Langmuir-Hinshelwood mechanism. [ABSTRACT FROM AUTHOR]

Fe/Mn@carbon cloth (CC) was successfully fabricated through high-temperature shock (HTS) technique and used as cathode modification in heterogeneous electro-Fenton (hetero-EF) process for methylisothiazolinone (MIT) degradation. The nanocrystalline on Fe/Mn@CC electrode is doped with Fe and Mn oxides and coated with carbon layer, which could markedly enhance the electrocatalysis with high electro-chemical active area and low resistance. Fe/Mn@CC modified cathode can efficiently in-situ produce and activate H 2 O 2 , showing high electrocatalytic activity to MIT degradation. The 95.2% MIT degradation with in 100 min were achieved under the condition of 30 mA current, 0.75 L min -1 aeration intensity and initial pH = 3. Based on the CV curves and stability test, the high degradation activity revealed the kinetically beneficial regeneration of Fe II /Mn II in Fe/Mn@CC and activation of H 2 O 2 . The electron transfer between Fe II/III and Mn II/III , together with the direct Fe II /Mn II regeneration on the cathode, could markedly promote the H 2 O 2 utilization, and eventually lead to MIT degradation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)