Open AccessUnderfocus Laser Induced Ni Nanoparticles Embedded Metallic MoN Microrods as Patterned Electrode for Efficient Overall Water Splitting
Author(s) -
Chen Yuke,
Wang Yijie,
Yu Jiayuan,
Xiong Guowei,
Niu Hongsen,
Li Yang,
Sun Dehui,
Zhang Xiaoli,
Liu Hong,
Zhou Weijia
Publication year - 2022
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.202105869
Subject(s) - overpotential , water splitting , materials science , oxygen evolution , electrode , electrocatalyst , electrolysis of water , chemical engineering , nanoparticle , reversible hydrogen electrode , electrolysis , nickel , nanotechnology , catalysis , working electrode , metallurgy , electrochemistry , chemistry , photocatalysis , biochemistry , engineering , electrolyte
Transition metal nitrides have shown large potential in industrial application for realization of the high active and large current density toward overall water splitting, a strategy to synthesize an inexpensive electrocatalyst consisting of Ni nanoparticles embedded metallic MoN microrods cultured on roughened nickel sheet (Ni/MoN/rNS) through underfocus laser heating on NiMoO 4 ·xH 2 O under NH 3 atmosphere is posited. The proposed laser preparation mechanism of infocus and underfocus modes confirms that the laser induced stress and local high temperature controllably and rapidly prepared the patterned Ni/MoN/rNS electrodes in large size. The designed Ni/MoN/rNS presents outstanding catalytic performance for hydrogen evolution reaction (HER) with a low overpotential of 67 mV to deliver a current density of 10 mA cm −2 and for the oxygen evolution reaction (OER) with a small overpotential of 533 mV to deliver 200 mA cm −2 . Density functional theory (DFT) calculations and Kelvin probe force microscopy (KPFM) further verify that the constructed interface of Ni/MoN with small hydrogen absorption Gibbs free energy (Δ G H* ) (−0.19 eV) and similar electrical conductivity between Ni and metallic MoN, which can explain the high intrinsic catalytic activity of Ni/MoN. Further, the constructed two‐electrode system (−) Ni/MoN/rNS||Ni/MoN/rNS (+) is employed in an industrial water‐splitting electrolyzer (460 mA cm −2 for 120 h), being superior to the performance of commercial nickel electrode.