Exceptional Performance of Hierarchical Ni–Fe (hydr)oxide@NiCu Electrocatalysts for Water Splitting

Abstract

The ever-increasing consumption of fossil fuels and resultant environmental issues, such as global warming, ozone layer depletion and acid rains, necessitate searching for clean energy sources. [1] Hydrogen is considered to be a promising alternative to fossil fuels by virtue of its high energy density and environmental-friendliness. [2] Renewable energy (such as electricity produced from photovoltaics and wind farms) powered water splitting provides an attractive method for sustainable production of hydrogen. [3] However, the two half electrochemical reactions involved in a water splitting process, namely, the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), are kinetically sluggish, leading to significant electrode overpotentials, and thus requires efficient electrocatalysts to improve energy efficiency. [3] Currently, precious-metal based electrocatalysts, such as Ir/Ru for OER and Pt for HER, could realize low overpotentials for water splitting. Unfortunately, the scarcity and high cost of these precious metals greatly prohibit their widespread applications.To this end, efforts have been devoted to searching for low-cost alternatives [4][5][6][7][8] and numerous Received: ((will be filled in by the editorial staff))Revised: ((will be filled in by the editorial staff))

Hollow Porous MnFe2O4 Sphere Grown on Elm‐Money‐Derived Biochar towards Energy‐Saving Full Water Electrolysis

“…The morphology of MnFe 2 O 4 /BC after 10 h OER test is shown in the inset of Figure 4 C, which exhibits no obvious change. Such overpotential and Tafel slope of the MnFe 2 O 4 /BC composites are lower than most of the recorded transitional metal catalysts as shown in Figure 4 D [7, 9–11, 13, 15–18, 20–24, 30, 56] …”

“…[4,5] Thus, it is crucialt od evelop non-precious catalysts that could efficientlyc atalyzew ater splitting. The non-preciousm etal catalysts are recognizeda sh aving broad developmentp rospects and can compensatef or the disadvantages of precious metal catalysts shortage of bifunctionality.A tp resent, low-cost efficient catalysts mainly focus on transition metal (TM) materials [6][7][8][9][10] including layered double hydroxides, [11][12][13][14] nitrides, [15][16][17] sulfides [18][19][20][21][22] and phosphides. [23][24][25][26] In addition, heteroatomdopedm aterials, such as N, Sa nd P-doped carbon, [27][28][29][30] were developed for HER and OER catalysts.…”

Reducing the Barrier Energy of Self‐Reconstruction for Anchored Cobalt Nanoparticles as Highly Active Oxygen Evolution Electrocatalyst

“…Though various OER electrocatalysts (e.g., perovskite oxides, noble metal, transition metal and their derivatives, etc.) have been proposed with acceptably high catalytic activities, their OER performances are still far from satisfactory . Among the metal‐based OER catalysts, the 3D transition metals (M) have received much attention as a promising OER electrocatalyst in alkaline medium due to the formation of oxy‐hydroxide (MOOH) intermediates which provide favorable active sites to OER .…”

Phosphorus and Yttrium Codoped Co(OH)F Nanoarray as Highly Efficient and Bifunctional Electrocatalysts for Overall Water Splitting

“…It is crucial and urgent to develop green and sustainable energy technology due to the growing energy demand, environmental pollution problem, and depletion of fossil fuel . Hydrogen is expected to be an ideal alternative to petroleum because of its high energy density and environmentally friendly nature . Water electrolysis is an appealing way to produce hydrogen, which could potentially store the intermittent energy resources (for example, solar and wind energy) .…”