A High Faraday Efficiency NiMoO₄ Nanosheet Array Catalyst by Adjusting the Hydrophilicity for Overall Water Splitting

Abstract

To obtain a highly active, stable, and binder‐free electrode based on transition‐metal compounds for water splitting, nickel foam‐supported 3D NiMoO4 nanosheet arrays modified with 0D Fe‐doped carbon quantum dots (Fe‐CQDs/NiMoO4/NF) are synthesized. The structure characterizations indicated that 0D Fe‐CQDs are evenly dispersed onto the NiMoO4 sheets of the arrays. The contact angle analysis confirmed that the surface hydrophilia of the arrays is improved after the 0D Fe‐CQDs are deposited 3D on the NiMoO4 sheets. Here, both the activity and durability in electrochemical water splitting are significantly enhanced with the Fe‐CQDs/NiMoO4/NF catalysts. At a current density of 10 mA cm−2, the resultant Fe‐CQDs/NiMoO4/NF revealed an overpotential of only 117 mV for the hydrogen evolution reaction (HER), a relatively low overpotential of 336 mV toward the oxygen evolution reaction (OER), and a Faraday efficiency of up to 99 %. This performance can be attributed to the unique 3D nanosheet array structure, the synergistic effect, and the optimal hydrophilia for gas evolution evolved from the electrode surface.

Plasma-Induced Defect Engineering and Cation Refilling of NiMoO4 Parallel Arrays for Overall Water Splitting

“…In Figure 4c, the Mo 3d spectrum reveals two peaks located at 231.7 and 234.8 eV with a spin−orbit splitting of 3.1 eV, which can be assigned to Mo 6+ . 49,50 After filling the vacancies by heteroatoms, the positive shift (0.4 eV for Fe and 0.6 eV for Pt) implies the interaction between the Fe/Pt and Mo species. Besides, the peaks located at 237.8 eV may be attributed to the partial surface elemental oxidation of Fe-NP-NMC/CC-10.…”

Copper mesh supported nickel nanowire array as a catalyst for the hydrogen evolution reaction in high current density water electrolysis

“…However, Ni NWs/Ni/CM materials greatly increase the specific surface area of nanostructures, enhancing the surface wettability, and thus improving the electrocatalytic activity. 30…”

Fabrication of a New Electrochemical Sensor Based on Bimetal Oxide for the Detection of Furazolidone in Biological Samples

“…Among metal oxides, binary metal oxide materials have attracted great interest in developing active electrode materials because of their feasible oxidation state and electrical conductivity [9]. Recently, transition series elements have been found as a promising material in the fields of supercapacitors [9], photodegradation [10], batteries [11], water splitting [12], and sensors [13]. As metal molybdates, MMoO 4 (M = Mn, Co, Zn, Fe, Ni, etc.)…”