Exploring the Heterostructure Engineering of SnS/NiCo2O4for Overall Water Splitting

G. John, S. Gopalakrishnan, Abhishek Sharan, M. Navaneethan, Jeganathan Kulandaivel, Nirpendra Singh, P. Justin Jesuraj

Research output: Contribution to journalArticlepeer-review

7 Scopus citations

Abstract

A bifunctional electrocatalyst with a low overpotential is a prerequisite for realizing efficient overall water splitting. In this scenario, the search for low-cost and non-precious electrocatalysts in electrolysis research leads to the employment of spinel oxides and chalcogenides. Herein, a heterostructure bifunctional electrocatalyst consisting of tin sulfide (SnS) nanosheets engrafted onto nickel cobalt oxide (NiCo2O4) nanoneedles suspended on nickel foam was prepared using the conventional hydrothermal method. The interface of SnS/NiCo2O4was found to contain half-metallic Sn-O bonds as evident from density functional theory calculations and X-ray photoelectron spectroscopy. Furthermore, SnS growth on NiCo2O4triggers new crystalline (0 2 1) planes and the vertical orientation of nanosheets enhancing the catalytic kinetics by exposing more surface S atoms, which provide a lower adsorption energy for hydrogen/oxygen moieties. The SnS/NiCo2O4catalyst on Ni foam exhibits overpotentials of 302 mV (at a current density of 20 mA cm-2) and 154 mV (at a current density of 20 mA cm-2) for oxygen and hydrogen evolution reactions, respectively, in a 1.0 M potassium hydroxide electrolyte. Furthermore, a potential of 1.57 V was required to attain a current density of 10 mA cm-2in the overall water-splitting process. Apart from this bifunctional ability, the catalyst shows good stability (>25 h) in the electrolyte. The growth of chalcogenides on spinel oxides paves a new way to realize efficient electrocatalysts with reduced adsorption energies.

Original languageBritish English
Pages (from-to)624-634
Number of pages11
JournalEnergy and Fuels
Volume37
Issue number1
DOIs
StatePublished - 5 Jan 2023

Fingerprint

Dive into the research topics of 'Exploring the Heterostructure Engineering of SnS/NiCo2O4for Overall Water Splitting'. Together they form a unique fingerprint.

Cite this