Metal‐Ion (Fe, V, Co, and Ni)‐Doped MnO₂ Ultrathin Nanosheets Supported on Carbon Fiber Paper for the Oxygen Evolution Reaction

Abstract

Manganese dioxides (MnO2) are considered one of the most attractive materials as an oxygen evolution reaction (OER) electrode due to its low cost, natural abundance, easy synthesis, and environmental friendliness. Here, metal‐ion (Fe, V, Co, and Ni)‐doped MnO2 ultrathin nanosheets electrodeposited on carbon fiber paper (CFP) are fabricated using a facile anodic co‐electrodeposition method. A high density of nanoclusters is observed on the surface of the carbon fibers consisting of doped MnO2 ultrathin nanosheets with an approximate thickness of 5 nm. It is confirmed that the metal ions (Fe, V, Co, and Ni) are doped into MnO2, improving the conductivity of MnO2. The doped MnO2 ultrathin nanosheet/CFP and the IrO2/CFP composite electrodes for OER achieve a low overpotential of 390 and 245 mV to reach 10 mA cm−2 in 1 m KOH, respectively. The potential of the doped composite electrode for long‐term OER at a constant current density of 20 mA cm−2 is much lower than that of the pure MnO2 composite electrode.

Construction of Defect‐Rich Ni‐Fe‐Doped K0.23MnO2 Cubic Nanoflowers via Etching Prussian Blue Analogue for Efficient Overall Water Splitting

“…XRD analysis (Figure 1a) showed that they can all be assigned to layered Birnessite-type δ-MnO 2 ( Small 2020, 16,1905223 Scheme 1. Schematic illustration of the synthetic process of Ni-Fe-K 0.23 MnO 2 CNFs-300.…”

Vanadium Doped Nickel Phosphide Nanosheets Self‐Assembled Microspheres as a High‐Efficiency Oxygen Evolution Catalyst

“…The superior catalytic performance should be attributed to the unique nanosheet-based microsphere structure and the synergistic effect between Ni and V, which is consistent with the previous reports. [43][44][45][46] The special 3D structure provides a large surface area, thus increasing the number of active sites. When combining with NF, the material has better electrical conductivity.…”

Strong Electronic Interaction in Dual‐Cation‐Incorporated NiSe2 Nanosheets with Lattice Distortion for Highly Efficient Overall Water Splitting

“…[22,23] For example, density functional theory (DFT) calculations show that the sites where Se atoms are at the edges of transition metal selenides are HER active sites. [29][30][31] In this case, it is expected that Exploring highly efficient and low-cost electrocatalysts for electrochemical water splitting is of importance for the conversion of intermediate energy. Indeed, incorporation of heterogeneous metal atoms can induce atomic distortions due to strain and result in additional exposed active sites.…”

“…[24] Furthermore, it has been shown that the heterogeneous metal atoms doping could optimize the hydrogen adsorption kinetic energy and improve the HER catalytic activity in comparison to monometallic ones. [29][30][31] In this case, it is expected that Exploring highly efficient and low-cost electrocatalysts for electrochemical water splitting is of importance for the conversion of intermediate energy. Moreover, the electronic interaction between each element in mono-cation-doped electrocatalysts has been always ignored.…”