Novel electrocatalysts for generating oxygen from alkaline water electrolysis

Abstract We have obtained spinel-type Co 3 O 4 and La-doped Co 3 O 4 in the form of thin film on Ni, using microwave-assisted synthesis, which dramatically exhibit very low overpotentials for the oxygen evolution reaction (OER). Investigations have shown that at the apparent current density of 100 mA cm −2 in 1 mol dm −3 KOH at 25 °C, the new electrodes, Co 3 O 4 (oxide loading = 3.4 ± 0.3 mg cm −2 ) and La-doped Co 3 O 4 (oxide loading = 2.8 ± 0.4 mg cm −2 ), produce overpotentials, 235 ± 7 and 224 ± 8 mV, respectively. Such low overpotentials for the OER, to our knowledge, have not been found on any mixed oxide electrode material reported in literature till today. Small La addition improved the BET surface area and porosity of the oxide catalyst powder and reduced the charge transfer resistance for the OER on the electrode made of oxide powder.

[1]  J. Singh,et al.  Electrocatalytic properties of new active ternary ferrite film anodes for O2 evolution in alkaline medium , 2002 .

[2]  S. Trasatti.  Electrodes of Conductive Metallic Oxides , 1981 .

[3]  Hong Lin,et al.  Electrophoretic deposition of ZnCo2O4 spinel and its electrocatalytic properties for oxygen evolution reaction , 2005 .

[4]  J. Singh,et al.  New NiFe2−xCrxO4 spinel films for O2 evolution in alkaline solutions , 2006 .

[5]  J. Bockris,et al.  Mechanism of oxygen evolution on perovskites , 1983 .

[6]  J. Bockris.  Electrodes of conductive metallic oxides, Part A : edited by S. Trasatti, Elsevier, Amsterdam, 1980, $76.75, 366 pages. , 1983 .

[7]  R. Singh,et al.  Synthesis of (La, Sr)CoO3 perovskite films via a sol–gel route and their physicochemical and electrochemical surface characterization for anode application in alkaline water electrolysis , 1996 .

[8]  M. H. Mendonça,et al.  Physicochemical and electrocatalytic properties of Li-Co3O4 anodes prepared by chemical spray pyrolysis for application in alkaline water electrolysis , 2004 .

[9]  Ning Li,et al.  Anodically electrodeposited Co+Ni mixed oxide electrode: preparation and electrocatalytic activity for oxygen evolution in alkaline media , 2004 .

[10]  K. Kalcher,et al.  Structural and Spectroelectrochemical Investigations of Sol-Gel Derived Electrochromic Spinel Co[sub 3]O[sub 4] Films , 1996 .

[11]  S. Trasatti.  Electrochemistry and environment: The role of electrocatalysis☆ , 1995 .

[12]  J. Bockris,et al.  Lanthanum Nickelate as Electrocatalyst: Oxygen Evolution , 1982 .

[13]  Khalid Fatih,et al.  CuxCo3−xO4/LaPO4-bonded Ni electrodes for oxygen evolution in alkaline solution: preparation, physicochemical properties, and electrochemical behavior , 1997 .

[14]  B. Orel,et al.  Characterization of spinel Co3O4 and Li-doped Co3O4 thin film electrocatalysts prepared by the sol–gel route , 2000 .

[15]  Ravindra Singh,et al.  Preparation of Perovskite‐Type Oxides of Cobalt by the Malic Acid Aided Process and Their Electrocatalytic Surface Properties in Relation to Oxygen Evolution , 1995 .

[16]  P. Ross,et al.  The Electrochemistry of novel materials , 1994 .

[17]  Saurabh Singh,et al.  Preparation of thin Co3O4 films on Ni and their electrocatalytic surface properties towards oxygen evolution , 1996 .

[18]  J. Bockris,et al.  The Electrocatalysis of Oxygen Evolution on Perovskites , 1984 .

[19]  A. Tavares,et al.  Effect of the partial replacement of Ni or Co by Cu on the electrocatalytic activity of the NiCo2O4 spinel oxide , 1999 .

[20]  J. Pandey,et al.  Sol-gel derived spinel MxCo3−xO4 (M=Ni, Cu; 0≤x≤1) films and oxygen evolution ☆ , 2000 .