CoO Promoted the Catalytic Activity of Nitrogen-Doped MoS2 Supported on Carbon Fibers for Overall Water Splitting

Liuqing Pang; Alexandre Barras; Yuan Zhang; Mohammed A Amin; Ahmed Addad; Sabine Szunerits; Rabah Boukherroub

doi:10.1021/acsami.9b09112

CoO Promoted the Catalytic Activity of Nitrogen-Doped MoS₂ Supported on Carbon Fibers for Overall Water Splitting

ACS Appl Mater Interfaces. 2019 Sep 4;11(35):31889-31898. doi: 10.1021/acsami.9b09112. Epub 2019 Aug 22.

Authors

Liuqing Pang¹, Alexandre Barras¹, Yuan Zhang¹, Mohammed A Amin^{2

3}, Ahmed Addad⁴, Sabine Szunerits¹, Rabah Boukherroub¹

Affiliations

¹ Université Lille, CNRS, Central Lille, ISEN, Université Valenciennes, UMR 8520, IEMN , F-59000 Lille , France.
² Materials and Energy Group, Department of Chemistry, Faculty of Science , Taif University , 888 Hawiya , 26571 Taif , Saudi Arabia.
³ Department of Chemistry, Faculty of Science , Ain Shams University , Abbassia, 11566 Cairo , Egypt.
⁴ Université Lille, CNRS, UMR 8207-UMET , F-59000 Lille , France.

PMID: 31402641
DOI: 10.1021/acsami.9b09112

Abstract

Non-noble metal electrocatalysts have recently witnessed increasing attention for the hydrogen evolution reaction (HER) in acidic electrolytes. However, in alkaline electrolytes, the slow kinetics of water splitting leads to poor HER activities. In this study, we describe the preparation of a hybrid material consisting of cobalt oxide (CoO) decorated on nitrogen-doped MoS₂ supported on carbon fibers (CoO/N-MoS₂/CF) through a two-step process combining hydrothermal technique and electrochemical deposition. The electrochemical properties of the CoO/N-MoS₂/CF electrocatalyst were assessed in alkaline medium. The results revealed that CoO/N-MoS₂/CF exhibits excellent bifunctional electrocatalytic activity for the HER and oxygen evolution reaction (OER). The CoO/N-MoS₂/CF delivered a current density of 10 mA/cm² at an overpotential of only 78 mV for the HER and a current density of 50 mA/cm² at 458 mV for the OER in 1.0 M KOH, performing better than many noble metal-free electrocatalysts. The enhanced catalytic properties of the hybrid nanomaterial could be ascribed to its hierarchical structure, and increased number of active sites, as well as the synergetic cooperation between its different components. Additionally, the CoO/N-MoS₂/CF nanomaterial was investigated as both cathode and anode for full water splitting in 1.0 M KOH. The water electrolyzer delivered a maximum current density of 53 mA cm^-2 at an applied cell voltage of 1.5 V, which is very favorable for overall water-splitting applications.

Keywords: CoO; HER; N-doped MoS; OER; carbon fiber; water splitting.