ADSORPTION PROPERTIES COMPOSITES OF POLYPIRROL-SPINEL NiCo2O4

Abstract

To interpret the experimentally established fact of the reduction of molecular oxygen on the surface of the multilayered polypyrrole/spinel (NiCo₂O₄) composite using quantum chemical calculations. The adsorption of oxygen molecules on surfaces of polypyrrole/spinel (NiCo₂O₄) composite is studied using ab initio embedded cluster calculations. The total energies of the molecular cluster of the composition Ni₂Co₄O₂₂C₈N₂H₂₈and the adsorption complexes Ni₂Co₄O₂₂C₈N₂H₂₈-O₂, Ni₂Co₄O₂₂C₁₂N₂H₂₈-O₂H-, Ni₂Co₄O₂₂C₁₂N₂H₂₈-2OH, Ni₂Co₄O₂₂C₁₂N₂H₂₈-H₂O₂H₂ were calculated. The electron density distribution between the power centers, bonds and atomic orbitals were determinate. In addition, the equilibrium lengths of adsorption bonds and adsorption energy of oxygen were clarified. It was shown for the first time that in polypyrrole/spinel (NiCo₂O₄) composite oxygen can be reduced by four electronic mechanisms. Practical significance. The obtained results can be used in experimental studies of catalytic activity of polypyrrole/spinel (NiCo₂O₄) composite and other composite materials based on transition metal oxides and electrically conductive polymers.