Effect of Ni Nanoparticles on HG Sheets Modified by GO on the Hydrogen Evolution Reaction

Abstract

Ni-based compounds are being explored as an alternative for Pt in hydrogen evolution reactions. In this work, phenylhydrazine-4-sulfonic acid is utilized in the reduction of graphene oxide to synthesize novel hydrophilic graphene, and electrodeposition is used to synthesize Ni–HG/NF composite cathodes from a nickel sulphamate bath containing suspended-sized hydrophilic graphene. The Ni–HG0.5/NF composite coatings reveal prominent activity on the hydrogen evolution reaction in alkaline solutions with a high exchange current density of 5.012 mA cm–2, a low Tafel slope of 81 mV dec–1, and small overpotentials of 30 and 140 mV to obtain current densities of 10 and 100 mA cm–2. These results are attributed to hydrophilic reform of hydrophilic graphene, enhanced charge transfer between Ni and hydrophilic graphene, and the strong intensity of Ni(111) of Ni–HG0.5/NF catalyst.

Ultrafine Ni-B nanoparticles for efficient hydrogen evolution reaction

“…Comparing with the characteristic peaks of Ni in other materials (Table S2), the binding energy of Ni in Ni-B-400 increases slightly, indicating that the electron density decreases. Additionally, the Ni 0 /Ni 2+ ratio can significantly account for the electrocatalytic HER [31,32]. The ratio of Ni 0 and Ni 2+ species is reckoned from the fitted peak area.…”

Electrocatalysts by Electrodeposition: Recent Advances, Synthesis Methods, and Applications in Energy Conversion

“…For instance, Du et al synthesized nickel-containing hydrophilic graphene composite on Ni foam Ni-HG X /NF electrocatalyst by co-electrodeposition method HER-to-H 2 conversion. [59] The Ni-HG 0.5 /NF composite achieved high current densities of 10 and 100 mA cm −2 at very low overpotentials of 30 and 140 mV, respectively, with a low Tafel slope 81 mV dec −1 in alkaline solutions for H 2 evolution. Ni-HG 0.5 /NF composite's catalytic activity was attributed to charge transfer between Ni and hydrophilic graphene and the strong intensity of Ni (111) of Ni-HG 0.5 /NF catalyst.…”

Electrochemical Reduction of CO2 to CO over Transition Metal/N‐Doped Carbon Catalysts: The Active Sites and Reaction Mechanism

“…It is well known that exposed metallic species such as Ni and Fe are prone to produce H 2 in aqueous solution due to their low Gibbs free energy to adsorb hydrogen intermediate. [ 110 , 111 ] Moreover, they may also dissolve to form ions under acidic conditions, not only destroying the structure of the M‐N‐C catalysts, but also competing for electrons with CO 2 reduction. In this situation, there exists a tradeoff between the high content of single metal atom sites and the formation of metal NPs for CO 2 RR.…”