“One Stone Five Birds” Plasma Activation Strategy Synergistic with Ru Single Atoms Doping Boosting the Hydrogen Evolution Performance of Metal Hydroxide

Abstract

Layered metal hydroxides (LMHs) are promising catalysts for oxygen evolution reaction. However, the hydrogen evolution reaction (HER) activity of LMHs is unsatisfactory due to their poor conductivity and limited active sites. Herein, taking Ni(OH)2 as demonstration, a novel “one stone five birds” plasma activation strategy synergistic with Ru single atoms (Ru SAs) doping is developed to boost the HER activity of Ni(OH)2 by constructing heterostructured β‐Ni(OH)2/Ni‐Ru SAs nanosheet arrays (NSAs). Benefiting from the structural/compositional features and optimized electronic state, the as‐obtained β‐Ni(OH)2/Ni‐Ru SAs NSAs exhibit splendid HER activity with a low overpotential of 16 mV at 10 mA cm−2 and a small Tafel slope of 21 mV dec−1 in alkaline solution. Excellent HER performance in alkaline seawater and neutral solutions are also demonstrated by the β‐Ni(OH)2/Ni‐Ru SAs NSAs. The plasma activation and Ru SAs doping play important roles in enhancing water adsorption and accelerating the kinetics of water dissociation. Density functional theory (DFT) calculations reveal that the introduction of Ru SAs in the system facilitates the generation of surface OH vacancies for providing more active sites as well as decreases the antibonding state density of the generated mid‐gap state for enhancing H adsorption strength toward the optimal range.

Hierarchical Superhydrophilic/Superaerophobic Ni(OH)2@NiFe-PBA Nanoarray Supported on Nickel Foam for Boosting the Oxygen Evolution Reaction

“…The morphologies and structures of Ni­(OH) 2 /NF and Ni­(OH) 2 @NiFe-PBA/NF were further recorded by TEM. Figure d illustrates a typical lamellar structure of Ni­(OH) 2 that is in agreement with a previous study . High-resolution TEM (HRTEM) images of Ni­(OH) 2 /NF in Figure e reveal lattice fringes with planar intervals of 0.23 and 0.27 nm, corresponding to the (101) and (100) planes of β-Ni­(OH) 2 , respectively.…”

“…Furthermore, it effectively increases the amount of the active sites for OER. The powerful interaction between the catalytically active material and the scaffold avoids the separation of the electrocatalyst from the scaffold during the release of gaseous products, while the fast electron transfer is guaranteed by the strong interfacial interaction. − Inspired by these facts, we tried initially to deposit β-Ni­(OH) 2 nanosheets on NF to obtain a precursor matrix with mechanical and electrochemical strength.…”

Strongly Coupled Heterostructured CoP/MoO2 as an Advanced Electrocatalyst for Urea-Assisted Water Electrolysis

“…Overall, this optimization of the electrode−electrolyte environment reduces bubble adhesion and promotes mass and electron transfer during electrochemical reactions. 42,43 In addition, electrochemical measurements were performed to estimate the HER activity of CoP/MoO 2 /NF utilizing three-electrode systems. Meanwhile, other electrodes were tested under the same conditions.…”

“…This property promotes the efficient release of gases during the process of overall water splitting. Overall, this optimization of the electrode–electrolyte environment reduces bubble adhesion and promotes mass and electron transfer during electrochemical reactions. , …”

Realization of electron-deficient Ru sites via Co4N coupling for synergistically enhanced alkaline hydrogen evolution

“…[18][19][20][21] Despite its exceptional performance in facilitating water dissociation, Ru suffers from a poor ability for H 2 desorption owing to its strong adsorption of H intermediates. [22][23][24][25] Therefore, balancing hydrogen adsorption and desorption over Ru sites is vitally important, but remains challenging.…”