A trinuclear cobalt-based coordination polymer as an efficient oxygen evolution electrocatalyst at neutral pH

Shaista Ibrahim; Kiran Shehzadi; Bushra Iqbal; Saghir Abbas; David R Turner; Muhammad Arif Nadeem

doi:10.1016/j.jcis.2019.03.018

A trinuclear cobalt-based coordination polymer as an efficient oxygen evolution electrocatalyst at neutral pH

J Colloid Interface Sci. 2019 Jun 1:545:269-275. doi: 10.1016/j.jcis.2019.03.018. Epub 2019 Mar 8.

Authors

Shaista Ibrahim¹, Kiran Shehzadi¹, Bushra Iqbal¹, Saghir Abbas², David R Turner³, Muhammad Arif Nadeem⁴

Affiliations

¹ Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
² Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan. Electronic address: drsaghirabbas@gmail.com.
³ School of Chemistry, Monash University, Clayton, Victoria 3800, Australia. Electronic address: david.turner@monash.edu.
⁴ Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan. Electronic address: manadeem@qau.edu.pk.

PMID: 30897422
DOI: 10.1016/j.jcis.2019.03.018

Abstract

The dearth of an efficient, robust, abundant and cost-effective water oxidation catalyst is debatably the major hurdle for the technological advancement of artificial photosynthesis devices. Herein, a three dimensional (3D) cobalt-based coordination polymer {[Co₃(pyz)(fa)₃(dmso)₂]·2H₂O}_n, (1) (pyz = pyrazine, fa = fumarate, dmso = dimethyl sulfoxide) has been synthesized and demonstrated to act as an efficient electrocatalyst towards water oxidation at neutral pH. Compound 1 displays a stair-like arrangement parallel to the b-axis, with the cobalt clusters arranged in a zigzag fashion, and contains small, honeycomb-like channels parallel to the c-axis. Compound 1 shows a remarkable activity for water oxidation and attains a current density of 1 mA.cm^-2 at low overpotential (η = 257 mV) with a Tafel slope value of 80.5 mV.dec^-1. This high performance of 1 in catalysing the water oxidation reaction is attributed to its unique 3-D architecture. The results of electrochemical investigations, including long-term and controlled potential electrolysis, are anticipated to guide the forthcoming advancement in creating efficient, cheap and noble metal (Pt/Ru/Ir) free catalysts for the water oxidation reaction.

Keywords: Cobalt; Electrocatalyst; Overpotential; Turnover frequency; Water oxidation.