Статья

Synthesis of Off‐Stoichiometric CoS Nanoplates from a Molecular Precursor for Efficient H<sub>2</sub>/O<sub>2</sub> Evolution and Supercapacitance

Charles GervasDepartment of Chemistry University of Zululand Private bag X1001 Kwa-Dlangezwa 3880 South AfricaMalik Dilshad KhanDepartment of Chemistry University of Zululand Private bag X1001 Kwa-Dlangezwa 3880 South AfricaSixberth MloweDepartment of Chemistry University of Zululand Private bag X1001 Kwa-Dlangezwa 3880 South AfricaChun‐yang ZhangDepartment of Chemistry Pittsburg State University Pittsburg, Kansas USAChen ZhaoDepartment of Chemistry Pittsburg State University Pittsburg, Kansas USARam K. GuptaDepartment of Chemistry Pittsburg State University Pittsburg, Kansas USAMatthew P. AkermanSchool of Chemistry and Physics University of KwaZulu-Natal Private Bag X01 Scottsville, Pietermaritzburg South AfricaPhilani MashaziDepartment of Chemistry Rhodes University PO Box 94 Grahamstown 6140 South AfricaTebello NyokongDepartment of Chemistry Rhodes University PO Box 94 Grahamstown 6140 South AfricaNeerish RevaprasaduDepartment of Chemistry University of Zululand Private bag X1001 Kwa-Dlangezwa 3880 South Africa

2019en

ABI

Аннотация

Abstract The development of cost‐effective and easily accessible bifunctional materials, which can be effectively used for energy storage and energy generation, is highly desirable. Herein, a new molecular precursor [ tris (morpholinodithiocarbamato)Co(III)] has been synthesized and the X‐ray crystal structure of the complex determined. The precursor was used to prepare oleylamine (OLA)‐capped cobalt sulfide nanoplatelets, using a facile hot injection method at two different temperatures (200 °C and 260 °C). The characterization of the samples shows that CoS synthesized at 200 °C is slightly sulfur rich, whereas CoS synthesized at 260 °C is slightly cobalt rich. The effect of off‐stoichiometry of CoS nanoplatelets on the energy generation and storage applications was studied. The oxygen evolution reaction catalytic performance of both samples indicate overpotentials of 307 and 276 mV as well as Tafel slopes of 96 and 82 mV/dec, respectively. Similarly, overpotentials of 132 and 153 mV were observed for the hydrogen evolution reaction, with Tafel slopes of 159 and 154 mV/dec, respectively. The capacitive behavior of the samples was also examined, and specific capacitance values of 298 and 440 F/g were obtained with cycling stabilities of 73 and 97 %, after 5000 cycles, respectively. The results indicate that sulfur‐deficient CoS can show superior performance for efficient energy generation and storage devices.

Перевод пока недоступен

Идентификаторы

DOI: 10.1002/celc.201900413

Цитирования и источники

Цитирований: 2Использованных источников: 0

Показатели — AkademScholar