Synergistic Effect of N ‐NiMoO4/Ni Heterogeneous Interface with Oxygen Vacancies in N‐NiMoO4/Ni/CNTs for Superior Overall Water Splitting

By a simple hydrothermal-H2 calcination method, the secondary aggregated metal nanoparticles with heterojunctions and abundant oxygen vacancies are loaded on carbon nanotubes (N-NiMoO4/Ni/CNTs). Operando Raman results reveal that Ni2+-OH* and C-H* as the active sites of HER process, γ-NiOOH serves as the active intermediates of OER process for N-NiMoO4/Ni/CNTs. AbstractThe exploring of economical, high-efficiency, and stable bifunctional catalysts for hydrogen evolution and oxygen evolution reactions (HER/OER) is highly imperative for the development of electrolytic water. Herein, a 3D cross-linked carbon nanotube supported oxygen vacancy (Vo)-rich N-NiMoO4/Ni heterostructure bifunctional water splitting catalyst (N-NiMoO4/Ni/CNTs) is synthesized by hydrothermal-H2 calcination method. Physical characterization confirms that Vo-rich N-NiMoO4/Ni nanoparticles with an average size of ≈19 nm are secondary aggregated on CNTs that form a hierarchical porous structure. The formation of Ni and NiMoO4 heterojunctions modify the electronic structure of N-NiMoO4/Ni/CNTs. Benefiting from these properties, N-NiMoO4/Ni/CNTs drives an impressive HER overpotential of only 46  mV and OER overpotential of 330 mV at 10 mA cm−2, which also shows exceptional cycling stability, respectively. Furthermore, the as-assembled N-NiMoO4/Ni/CNTs||N-NiMoO4/Ni/CNTs electrolyzer reaches a cell voltage of 1.64  V at 10 mA cm−2 in alkaline solution. Operando Raman analysis reveals that surface r...

Source: Small - April 7, 2023 Category: Nanotechnology Authors: Guang ‐Lan Li, Xiang‐Yue Qiao, Ying‐Ying Miao, Tian‐Yu Wang, Fei Deng Tags: Research Article Source Type: research