Theoretical Insights into the Hydrogen Evolution Reaction on the Ni3N Electrocatalyst

Abstract

Ni-based catalysts are attractive alternatives to noble metal electrocatalysts for the hydrogen evolution reaction (HER). Herein, we present a dispersion-corrected density functional theory (DFT-D3) insight into HER activity on the (111), (110), (001), and (100) surfaces of metallic nickel nitride (Ni3N). A combination of water and hydrogen adsorption was used to model the electrode interactions within the water splitting cell. Surface energies were used to characterise the stabilities of the Ni3N surfaces, along with adsorption energies to determine preferable sites for adsorbate interactions. The surface stability order was found to be (111) < (100) < (001) < (110), with calculated surface energies of 2.10, 2.27, 2.37, and 2.38 Jm−2, respectively. Water adsorption was found to be exothermic at all surfaces, and most favourable on the (111) surface, with Eads = −0.79 eV, followed closely by the (100), (110), and (001) surfaces at −0.66, −0.65, and −0.56 eV, respectively. The water splitting reaction was investigated at each surface to determine the rate determining Volmer step and the activation energies (Ea) for alkaline HER, which has thus far not been studied in detail for Ni3N. The Ea values for water splitting on the Ni3N surfaces were predicted in the order (001) < (111) < (110) < (100), which were 0.17, 0.73, 1.11, and 1.60 eV, respectively, overall showing the (001) surface to be most active for the Volmer step of water dissociation. Active hydrogen adsorption sites are also presented for acidic HER, evaluated through the ΔGH descriptor. The (110) surface was shown to have an extremely active Ni–N bridging site with ΔGH = −0.05 eV.

Engineering Metallic Heterostructure Based on Ni3N and 2M‐MoS2 for Alkaline Water Electrolysis with Industry‐Compatible Current Density and Stability

“…As shown in Figure , it is revealed that the active Ni sites of Ni 3 N@2M‐MoS 2 system (Figure 4a,b) exhibit lower energy barrier (0.653 eV) for water decomposition, compared with Ni 3 N (111) (0.73 eV) and 2M‐MoS 2 (002) (1.84 eV) reported recently. [ 37 ] Consequently, the Ni 3 N@2M‐MoS 2 composite accelerates water dissociation to provide hydrogen source with lower energy barrier for HER under alkaline media. From the microscopic view, the apparent alkaline HER activity is governed by two factors: the energy barrier of water dissociation and appropriate hydrogen adsorption/desorption.…”

Electronegativity Enhanced Strong Metal–Support Interaction in Ru@F–Ni3N for Enhanced Alkaline Hydrogen Evolution

“…Nickel nitride (Ni 3 N) and its nanocomposites have demonstrated excellent application potential for water electrolysis due to its corrosion resistance, Pt-like electronic structure, and high conductivity. , However, the catalytic activity of Ni 3 N-based catalysts still needs to be further improved. As reported by Cross et al, the activation energy ( E a ) value for water splitting on the Ni 3 N (001) surface was predicted as low as 0.17 eV, indicating the fast initial water dissociation process on the Ni 3 N (001) surface . Since the water molecule can be dissociated on the Ni 3 N surface, it can be reasonably speculated that the H adsorption Gibbs free energy (Δ G H* ) would be an important indicator to evaluate the water electrolysis ability of Ni 3 N-based catalysts in alkaline media.…”

Recent Advances in Ni‐Based Electrocatalysts for Hydrogen Evolution Reaction

“…For example, Dzade et al studied the HER activity on the (111), (110), (001), and (100) surfaces of nickel nitride (Ni 3 N) by dispersion‐corrected DFT. [ 108 ] The calculated water adsorption energies indicate that the (111) surface shows the most favorable water adsorption. In addition, the calculated activation energies indicate that the (001) surface has the most active Volmer step for water dissociation.…”