Selenium vacancy-rich CoSe₂ ultrathin nanomeshes with abundant active sites for electrocatalytic oxygen evolution

Abstract

CoSe2 ultrathin nanomeshes with abundant selenium vacancies have been synthesized through a plasma-exfoliation method and exhibit an excellent OER performance.

Recent Progress of Vacancy Engineering for Electrochemical Energy Conversion Related Applications

“…Zhang and co‐workers designed CoSe 2 ultrathin nanomesh materials with rich selenium vacancies (CoSe 2 UNMvac) via a plasma‐exfoliation treatment of layered hybrids (Figure 12f). [ 196 ] The prepared CoSe 2 UNMvac exhibited excellent electrocatalytic activities for OER with lower overpotential of 284 mV to deliver 10 mA cm −2 compared with the activities of CoSe 2 nanoparticles (466 mV@10 mA cm −2 ) and CoSe 2 nanosheets (343 mV@10 mA cm −2 ), indicating that the introduction of Se vacancy facilitated the enhancement of catalytic activity by favoring the transformation of surface CoSe 2 into highly active CoOOH.…”

“…In addition to CO, HCOOH is a valued liquid chemical for CO 2 RR, and can be used for hydrogen storage and transport. [ 106,196 ] Gong and co‐workers [ 197 ] found that moderate content of oxygen vacancies in SnO x results in a more active surface and can inhibit undesirable HER. Oxygen vacancy also could tune the bond strength between intermediates of HCOO* and SnO x , resulting in excellent electrocatalytic activity and selectivity for the production of HCOOH.…”

Design and operando/in situ characterization of precious‐metal‐free electrocatalysts for alkaline water splitting

“…Analogously, ultrathin CoSe 2 nanomeshes (CoSe 2 UNM vac ) catalyst with abundant selenium vacancies was fabricated via plasma treatment. 52 The generation of selenium vacancies with the exposure of abundant catalytic active sites resulted in improved catalytic performance. Lately, Qiao and co-workers prepared highly efficient HER electrocatalysts with controllable phosphorus vacancies in nickel phosphides via readily thermal annealing using excessive sodium hypophosphite.…”

Anion Vacancy Engineering in Electrocatalytic Water Splitting

“…Moreover, some other spectroscopic techniques, including electron paramagnetic resonance (EPR) and electron spin resonance (ESR) spectra, conduce to the analysis of the electronic environment around vacancies [38] . For example, CoSe 2 UNM vac shows an obvious EPR resonance and the calculated g value of 2.002, indicating the existence of Se vacancies (Figure 3c) [39] . And BiO 2‐x exhibits an obvious signal at the g value of 2.0 in the ESR spectrum, suggesting the presence of O vacancies in its structures (Figure 3d) [40]…”