Single‐Atom Co‐Decorated MoS₂ Nanosheets Assembled on Metal Nitride Nanorod Arrays as an Efficient Bifunctional Electrocatalyst for pH‐Universal Water Splitting

Abstract

The commercialization of electrochemical water splitting technology requires electrocatalysts that are cost‐effective, highly efficient, and stable. Herein, an advanced bifunctional electrocatalyst based on single‐atom Co‐decorated MoS2 nanosheets grown on 3D titanium nitride (TiN) nanorod arrays (CoSAs‐MoS2/TiN NRs) has been developed for overall water splitting in pH‐universal electrolytes. When applied as a self‐standing cathodic electrode, the CoSAs‐MoS2/TiN NRs requires overpotentials of 187.5, 131.9, and 203.4 mV to reach a HER current density of 10 mA cm–2 in acidic, alkaline, and neutral conditions, respectively, which are superior to the most previously reported non‐noble metal HER electrocatalysts at the same current density. The CoSAs‐MoS2/TiN NRs anodic electrode also shows low OER overpotentials of 454.9, 340.6, and 508.0 mV, respectively, at a current density of 10 mA cm–2 in acidic, alkaline, and neutral mediums, markedly outperforming current OER catalysts reported elsewhere. More importantly, an electrolyzer delivered from the cathodic and anodic CoSAs‐MoS2/TiN NRs electrodes exhibits an extraordinary overall water splitting performance with good stability and durability in pH‐universal conditions.

Ru-Doped CuO/MoS2 Nanostructures as Bifunctional Water-Splitting Electrocatalysts in Alkaline Media

“…This demanded development of suitable OER/HER catalysts capable of reducing activation energy involved in the water-splitting process. In this regard, platinum (Pt) and Ru/Ir exhibited outstanding electrocatalytic activity in HER and OER, respectively. However, high cost, low availability, and poor stability mark significant limitations for their commercial and technological applications.…”

Co-doped MoS2nanosheet: a stable and pH-universal electrocatalyst for an efficient hydrogen evolution reaction

“…29–31 The two other peaks at 779.48 eV and 801.78 eV may be attributed to the strong interaction between the Co–Mo bond and the cobalt nanoparticles and MoS 2 phase, respectively. 32–34…”

Focused Plasma- and Pure Water-Enabled, Electrode-Emerged Nanointerfaced NiCo Hydroxide–Oxide for Robust Overall Water Splitting

“…It is found that there is a relatively large charge transfer between NiCo 2 O 4 and NiCo­(OH) 2 . The charge is mainly transferred from NiCo­(OH) 2 to NiCo 2 O 4 , which leads to the strong interlayer interaction. According to the Tafel slope value, the catalytic HER process using the NiCo 2 O 4 @NiCo­(OH) 2 /PNCF electrode follows the Volmer–Heyrovsky mechanism, whereas the Heyrovsky step is the rate-determining step: …”

“…According to the Tafel slope value, the catalytic HER process using the NiCo 2 O 4 @NiCo­(OH) 2 /PNCF electrode follows the Volmer–Heyrovsky mechanism, whereas the Heyrovsky step is the rate-determining step:…”