1D-CoSe 2 nanoarray: a designed structure for efficient hydrogen evolution and symmetric supercapacitor characteristics

• Published in: Dalton transactions : an international journal of inorganic chemistry 2020-10, Vol.49 (40), p.14191-14200
• Main Authors: Rabani, Iqra, Hussain, Sajjad, Vikraman, Dhanasekaran, Seo, Young-Soo, Jung, Jongwan, Jana, Atanu, Shrestha, Nabeen K., Jalalah, Mohammed, Noh, Yong-Young, Patil, Supriya A.
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/D0DT02548H

Direct growth of self-supported one-dimensional (1D) nanorod arrays on conducting substrates is highly attractive for electrocatalysis, due to their unique shape, size, and length. In this work, a facile and simple two-step method was employed to synthesize 1D-CoSe 2 nanoarrays on titanium (Ti) foil via a wet chemical ion-exchange approach. The as-synthesized 1D-CoSe 2 nanoarrays were directly used as electrode materials for hydrogen evolution reaction and supercapacitors. As an electrocatalyst, the optimized 1D-CoSe 2 ( t ex -48 h) nanoarray exhibits excellent hydrogen evolution properties with a small Tafel slope of 78 mV dec −1 , low overpotentials of 41 mV@1 mA cm −2 and 216 mV@10 mA cm −2 , and extended robust performance for 25 h. Moreover, for a symmetric device, it delivers a maximum specific capacitance of 152 F g −1 at 0.5 A g −1 and a better energy density of 21.1 W h kg −1 at a power density of 0.5 kW kg −1 . Also, the symmetric device capacity retention behavior achieves ∼96.8% of the initial result after 5000 cycles, revealing the good stability of the electrode. Our findings offer a new way to further the development of high-performance energy devices.