Non-precious Co3O4 nano-rod electrocatalyst for oxygenreduction reaction in anion-exchange membranefuelcells

Solar absorptance of copper–cobalt oxide thin film coatings with nano-size, grain-like morphology: Optimization and synchrotron radiation XPS studies

“…In a relatively low temperature synthesis process (under 100 o C), the cobalt oxide surface synthesized using cobalt chloride precursor has already shown a differentiation in the oxidation states composition by the presence of both Co(II) and Co(III) species [41]. In a higher temperatures treatment of around 330-350 o C, the mixed oxidation states of cobalt (Co 3 O 4 ) which has a normal spinel crystal structure based on a close-packed face centered cubic configuration of O 2-ions where Co(II) ions occupy the one-eighth of the tetrahedral A-sites and Co(III) ions occupy one-half of the octahedral B sites are detected [42]. Further, the octahedral Co(III) ions here have a more significant role determining the surface activity rather than tetrahedral Co(II) [42,43] In a copper-cobalt mixed oxides system, the Co(II) ions are partially substituted by Cu 2+ ions [8,45].…”

“…In a higher temperatures treatment of around 330-350 o C, the mixed oxidation states of cobalt (Co 3 O 4 ) which has a normal spinel crystal structure based on a close-packed face centered cubic configuration of O 2-ions where Co(II) ions occupy the one-eighth of the tetrahedral A-sites and Co(III) ions occupy one-half of the octahedral B sites are detected [42]. Further, the octahedral Co(III) ions here have a more significant role determining the surface activity rather than tetrahedral Co(II) [42,43] In a copper-cobalt mixed oxides system, the Co(II) ions are partially substituted by Cu 2+ ions [8,45]. If Cu 2+ ions and octahedral Co(III) ions are present in the copper-cobalt oxide system, then the oxide could be represented by the Cu 2+ Co 2 III O 4 , a form of copper-cobalt spinel structure.…”

Voltammetric Studies of the Mechanism of the Oxygen Reduction in Alkaline Media at the Spinels Co3O4and NiCo2O4

“…Three recent papers from our group [16][17][18] report oxygen reduction at GDE based on NiCo 2 O 4 catalyst without graphitic carbon. A number of papers have also reported the behavior of nanostructured Co 3 O 4 and NiCo 2 O 4 for oxygen reduction 12,13,[19][20][21][22][23][24][25][26][27][28][29][30][31][32] but the assessment of these data is often hampered by the absence of data at 'standard' surfaces, such as Pt, graphitic carbon, or the uncoated glassy carbon surface, for comparison. The inclusion of such standard surfaces enables accurate comparison of the limiting currents and onset potentials * Electrochemical Society Fellow.…”

Active Species of Sulfated Metal Oxide Catalyst for Propane Dehydrogenation

“…From Fig. 6(a), the peaks for Co 3 were observed at around 779.4 eV and 795.2 eV 19) . In the S2p spectrum, the peak for sulfate ion of SO4 2-was confirmed at 169.7 eV.…”