Fe-doped porous Co3O4 nanosheets with highly efficient catalytic performance for soot oxidation

Enhanced toluene sensing performances over commercial Co3O4 modulated by oxygen vacancy via NaBH4-assisted reduction approach

“…Both Co 3 O 4 and Co 3 O 4 -R-5 present two peaks located at 529.6 and 533.1 eV, which are assigned to metal–oxygen bonds (lattice oxygen, O L ) and surface-adsorbed oxygen (O C ), as well as a peak at 531.3 eV derived from the oxygen atoms around an oxygen vacancy (O V ). 45 Notably, compared with the O V peak of Co 3 O 4 , the molar percentage of O V in Co 3 O 4 -R-5 increased from 21.31% to 63.28% (Table 1), further confirming that the reduction of Co 3+ ions to Co 2+ ions resulted in the formation of oxygen vacancies. It is well known that the surface mobility and activation ability of oxygen are distinctly enhanced by increasing the number of surface oxygen vacancies.…”

High-performance Ce doped three-dimensional ordered macroporous Co-based catalysts on CO oxidation

“…7a, 3D-Co 16 Ce 1 O y shows lower adsorption energy for O 2 ( E ads O 2 = −0.773 eV) than 3D-Co 3 O 4 ( E ads O 2 = −0.679 eV), indicating that 3D-Co 16 Ce 1 O y can utilize O 2 more easily and supplement the consumption of reactive oxygen species during CO oxidation. 15 In addition, the adsorption energy of CO by 3D-Co 16 Ce 1 O y ( E ads CO = −1.267 eV) is lower than that by 3D-Co 3 O 4 ( E ads CO = −0.957 eV). Under an absolute O 2 dominant condition (reaction gas: 1 vol% CO/10 vol% O 2 /89 vol% N 2 vol%), the adsorption capacity of 3D-Co 16 Ce 1 O y for CO ( E ads CO = −1.267 eV) is higher than that for O 2 ( E ads O 2 = −0.773 eV).…”

“…In addition to controlling the crystal surface of Co 3 O 4 , suitable metal ion doping can promote the formation of oxygen vacancies and improve the intrinsic activity of the catalyst. 15 For instance, Zhou et al 16 prepared a Cu-doped Co-based catalyst (Co 3 O 4 -Cu x ) by a hydrothermal method, and the CO conversion rate of the optimal Co 3 O 4 -Cu 2 was 100% at 120 °C. Cerium dioxide (CeO 2 ) is a common support catalyst material and an excellent dopant owing to its good oxygen storage capacity (OSC) and oxygen migration ability.…”

Recent Progress on Density Functional Theory Calculations for Catalytic Control of Air Pollution

“…(A) Surface energy (a), formation energy of oxygen vacancy (b), and adsorption energy of O 2 (c) over Co 3 O 4 -111 and CoFe-111. (Reproduced with permission from ref . Copyright 2022 Elsevier.)…”