摘要： A series of calcium-manganese oxides (Ca-Mn-O) were prepared through thermal decomposition of carbonate solid-solution precursors and investigated as electrocatalysts for oxygen reduction reaction (ORR). The synthesized crystalline Ca-Mn-O compounds, including perovskite-type CaMnO 3 , layered structured Ca 2 Mn 3 O 8 , post-spinel CaMn 2 O 4 and CaMn 3 O 6 , presented similar morphologies of porous microspheres with agglomerated nanoparticles. Electrochemical results, surface analysis, and computational studies revealed that the catalytic activities of Ca-Mn-O oxides, in terms of onset potential, reduction current, and transferred electron number, depended strongly on both the surface Mn oxidation state and the crystallographic structures. Remarkably, the as-synthesized CaMnO 3 and CaMn 3 O 6 exhibited considerable activity and enabled an apparent quasi 4-electron oxygen reduction with low yield of peroxide species in alkaline solutions, suggesting their potential applications as cheap and abundant ORR catalysts. Calcium-manganese oxides with porous microspheres exhibit considerable activity for the electrocatalytic quasi-4 electron oxygen reduction. 出版日期： 2012-11-26 資源來源： Royal Society of Chemistry 識別號： ISSN: 2041-6520 識別號： EISSN: 2041-6539 識別號： DOI: 10.1039/c2sc21475j
