Spinel Cobalt Titanium Binary Oxide as an All-Non-Precious Water Oxidation Electrocatalyst in Acid

Sengeni Anantharaj; Kannimuthu Karthick; Subrata Kundu

doi:10.1021/acs.inorgchem.9b00868

Spinel Cobalt Titanium Binary Oxide as an All-Non-Precious Water Oxidation Electrocatalyst in Acid

Inorg Chem. 2019 Jul 1;58(13):8570-8576. doi: 10.1021/acs.inorgchem.9b00868. Epub 2019 Jun 7.

Authors

Sengeni Anantharaj^{1

2}, Kannimuthu Karthick^{1

2}, Subrata Kundu^{1

2}

Affiliations

¹ Academy of Scientific and Innovative Research (AcSIR) , Ghaziabad , Uttar Pradesh 201002 , India.
² Materials Electrochemistry Division (MED) , CSIR-Central Electrochemical Research Institute (CECRI) , Karaikudi , Tamil Nadu 630006 , India.

PMID: 31185540
DOI: 10.1021/acs.inorgchem.9b00868

Abstract

Replacing precious water oxidation electrocatalysts used in proton exchange membrane (PEM) water electrolyzers with the nonprecious and abundant electrocatalysts is still a poorly addressed issue in the field of hydrogen generation in acidic medium through water electrolysis. Herein we report such an all-nonprecious binary spinel metal oxide the "cobalt titanate" (Co₂TiO₄) as an efficient alternate to expensive IrO₂ and RuO₂ for PEM water electrolyzer. The synthesized Co₂TiO₄ octahedral nanocrystals of size 50 to 210 nm showed excellent oxygen evolution reaction (OER) activity in 0.5 M H₂SO₄, which was comparable to IrO₂ and better than spinel Co₃O₄ when examined under identical experimental conditions. Overpotential of just 513 mV was sufficient enough to drive a kinetic current density of 10 mA cm^-2, which is a significant figure of merit as far as acidic water oxidation electrocatalysis is concerned.