Zong, W., Lian, R., He, Guanjie , Guo, H., Ouyang, Y., Wang, J., Lai, F., Miao, Y.-E., Rao, D., Brett, D. and Liu, T. (2020) Vacancy engineering of group VI anions in NiCo<inf>2</inf>A<inf>4</inf> (A = O, S, Se) for efficient hydrogen production by weakening the shackles of hydronium ion. Electrochimica Acta, 333 .
Full content URL: http://doi.org/10.1016/j.electacta.2019.135515
Full text not available from this repository.
Item Type: | Article |
---|---|
Item Status: | Live Archive |
Abstract
Hydrogen evolution reaction (HER) has been severely suppressed by the first proton adsorption step, due to the “shackles” of the surrounding water in the form of hydronium ions (H13O6+). Here, it has been found anionic vacancies in NiCo2A4 (A = O, S, Se) can weaken the shackles of surrounding water in H13O6+, resulting into efficient capture of H+ to form a H+-enriched field. Taking selenium vacancy-rich NiCo2Se4 nanowires on nitrogen-doped carbon nanofibers as an example, it displays higher electrocatalytic activities with low overpotential of 168 mV at 10 mA cm−2 and a Tafel slope of 49.8 mV dec−1. The HER performance is strongly related to the anionic vacancy size, the larger the anionic vacancy size is (VSe > VS > VO), the higher the HER activity does. Guided by density functional theory calculations, it is found that the point defect structures can not only strengthen its interfacial linkage force with H+ by weakening the hydration force of contiguous hydronium ion, but also increase its charge density for efficient electron transfer to adsorbed H+. Therefore, this work creates a useful strategy to optimize the HER performance of traditional bimetallic compounds by engineering the solid-liquid-gas three-phase interfacial interaction.
Additional Information: | cited By 0 |
---|---|
Divisions: | College of Science > School of Chemistry |
ID Code: | 39491 |
Deposited On: | 16 Jan 2020 16:26 |
Repository Staff Only: item control page