Nickel-cobalt bimetallic sulfide NiCo 2 S 4 nanostructures for a robust hydrogen evolution reaction in acidic media.

Autor: Aftab U; Mehran University of Engineering and Technology 7680 Jamshoro Sindh Pakistan umair.aftab@faculty.muet.edu.pk., Tahira A; Department of Science and Technology, Campus Norrkoping, Linkoping University SE-60174 Norrkoping Sweden., Mazzaro R; Institute for Microelectronics and Microsystems, Italian National Research Council, Section of Bologna Via Piero Gobetti 101 40129 Bologna Italy., Morandi V; Institute for Microelectronics and Microsystems, Italian National Research Council, Section of Bologna Via Piero Gobetti 101 40129 Bologna Italy., Ishaq Abro M; Mehran University of Engineering and Technology 7680 Jamshoro Sindh Pakistan umair.aftab@faculty.muet.edu.pk., Baloch MM; Mehran University of Engineering and Technology 7680 Jamshoro Sindh Pakistan umair.aftab@faculty.muet.edu.pk., Yu C; State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun People's Republic of China., Ibupoto ZH; Dr M. A. Kazi Institute of Chemistry, University of Sindh Jamshoro 76080 Sindh Pakistan zaffar.ibhupoto@usindh.edu.pk.
Jazyk: angličtina
Zdroj: RSC advances [RSC Adv] 2020 Jun 15; Vol. 10 (37), pp. 22196-22203. Date of Electronic Publication: 2020 Jun 15 (Print Publication: 2020).
DOI: 10.1039/d0ra03191g
Abstrakt: There are many challenges associated with the fabrication of efficient, inexpensive, durable and very stable nonprecious metal catalysts for the hydrogen evolution reaction (HER). In this study, we have designed a facile strategy by tailoring the concentration of precursors to successfully obtain nickel-cobalt bimetallic sulfide (NiCo 2 S 4 ) using a simple hydrothermal method. The morphology of the newly prepared NiCo 2 S 4 comprised a mixture of microparticles and nanorods, which were few microns in dimension. The crystallinity of the composite sample was found to be excellent with a cubic phase. The sample that contained a higher amount of cobalt compared to nickel and produced single-phase NiCo 2 S 4 exhibited considerably improved HER performance. The variation in the salt precursor concentration during the synthesis of a material is a simple methodology to produce a scalable platinum-free catalyst for HER. The advantageous features of the multiple active sites of cobalt in the CN-21 sample as compared to that for pristine CoS and NiS laid the foundation for the provision of abundant active edges for HER. The composite sample produced a current density of 10 mA cm -2 at an overpotential of 345 mV. Also, it exhibited a Tafel value of 60 mV dec -1 , which predominantly ensured rapid charge transfer kinetics during HER. CN-21 was highly durable and stable for 30 hours. Electrochemical impedance spectroscopy showed that the charge transfer resistance was 21.88 ohms, which further validated the HER polarization curves and Tafel results. CN-21 exhibited a double layer capacitance of 4.69 μF cm -2 and a significant electrochemically active surface area of 134.0 cm 2 , which again supported the robust efficiency for HER. The obtained results reveal that our developed NiCo 2 S 4 catalyst has a high density of active edges, and it is a non-noble metal catalyst for the hydrogen evolution reaction. The present findings provide an alternative strategy and an active nonprecious material for the development of energy-related applications.
Competing Interests: Authors declare no conflict of interest in this research work.
(This journal is © The Royal Society of Chemistry.)
Databáze: MEDLINE
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