Carbon-confinement modulated interfacial water structure for accelerated dissociation kinetics towards hydrogen evolution
Fanpeng Cheng * , Yue Yu , Yulu Wan , Dashuai Wang , Shangqing Chen , Jingfang Zhang , Huijuan Guo , Yang Xia , Yi Huang , Lijuan Shi , Liwei Cheng* , Qun Yi*
Chemical Engineering Journal 520 (2025) 166181
https://doi.org/10.1016/j.cej.2025.166181
Low-cost and structurally tunable nickel sulfide is considered highly desirable electrocatalysts for alkaline hydrogen evolution reaction (HER). However, sluggish water dissociation, attributed to the unfavorable electrode-electrolyte dynamic interfacial water structure, limits the electrocatalytic performance. Herein, we construct carbon-confined Ni3S4 arrays (Ni3S4@C) by carbonization and subsequent etching step. Benefiting from the strong electron transferability and confinement effect, the Ni3S4@C shows improved HER performance, exhibiting the overpotentials of 49 and 415 mV to reach 10 and 1000 mA cm− 2, respectively, surpassing commercial Pt/C catalyst at higher current densities (>500 mA cm− 2). Characterization results uncover that the carbon layer triggered the generation of electron-rich Ni species due to the occurrence of electron transfer within Ni3S4@C. In-situ spectroscopy and calculated analyses indicate that the carbon-confined Ni3S4 modulates the interfacial water structure with abundant free water, preventing excessively robust hydrogen-bonding networks, which enables rapid water dissociation at Ni sites and optimal hydrogen adsorption energy at S sites for the boosted alkaline HER performance.
