Novel FexCr2-x(MoO4)(3) electrocatalysts for oxygen evolution reaction

作者：Singh R N^*; Kumar M; Sinha A S K

来源：International Journal of Hydrogen Energy, 2012, 37(20): 15117-15124.

DOI：10.1016/j.ijhydene.2012.07.114

• Ternary mixed oxides
• Oxygen evolution reaction
• Mixed metal molybdates
• Impedance spectroscopy

Transition metal mixed oxides of Fe, Cr and Mo with nominal compositional formula, FexCr2-x(MoO4)(3) (x = 0, 0.25, 0.50 and 0.75) have been obtained by a co-precipitation method and investigated for their structural and electrocatalytic properties by XRD, TEM, XPS, BET, electrochemical impedance spectroscopy and anodic Tafel polarization. Results show that introduction of Fe for Cr from 0.25 to 0.75 mol into the Cr-2(MoO4)(3) matrix improved the electrocatalytic activity toward the O-2 evolution reaction (OER) in 1 M KOH considerably; the magnitude of improvement being maximum with 0.5 mol Fe. Values of the Tafel slope were close to 35 mV at low and 2.303RT/F at high overpotentials on Fe-substituted oxides. The OER follows nearly second order kinetics in OH- concentration at low overpotentials.

• 出版日期2012-10