1c:I[419806,["/_next/static/chunks/bb923814e1f4d2e9.js","/_next/static/chunks/dd3ee9f5b7716ca6.js","/_next/static/chunks/4204a0ae82542ca8.js","/_next/static/chunks/30036bedc5269936.js","/_next/static/chunks/6e1aa89a642f40be.js","/_next/static/chunks/cd5e572bc3e4eb92.js","/_next/static/chunks/8ffd0b71567920d8.js","/_next/static/chunks/67ea6dfd21f16c5f.js","/_next/static/chunks/24eb4379f68013fd.js","/_next/static/chunks/b8cd775ffdf935bd.js","/_next/static/chunks/983103cd9eb7b428.js","/_next/static/chunks/d4ac9dcf27f6ff52.js","/_next/static/chunks/294b9525248c8e5f.js"],"default"] 1d:T47f,A facile and novel one‐step method of growing nickel‐cobalt layered double hydroxide (Ni‐Co LDH) hybrid films with ultrathin nanosheets and porous nanostructures on nickel foam is presented using cetyltrimethylammonium bromide as nanostructure growth assisting agent but without any adscititious alkali sources and oxidants. As pseudocapacitors, the as‐obtained Ni‐Co LDH hybrid film‐based electrodes display a significantly enhanced specific capacitance (2682 F g −1 at 3 A g −1 , based on active materials) and energy density (77.3 Wh kg −1 at 623 W kg −1 ), compared to most previously reported electrodes based on nickel‐cobalt oxides/hydroxides. Moreover, the asymmetric supercapacitor, with the Ni‐Co LDH hybrid film as the positive electrode material and porous freeze‐dried reduced graphene oxide (RGO) as the negative electrode material, exhibits an ultrahigh energy density (188 Wh kg −1 ) at an average power density of 1499 W kg −1 based on the mass of active material, which greatly exceeds the energy densities of most previously reported nickel or cobalt oxide/hydroxide‐based asymmetric supercapacitors.1e:T472,A fundamental understanding of the origin of oxygen evolution reaction (OER) activity of transition-metal-based electrocatalysts, especially for single precious metal atoms supported on layered double hydroxides (LDHs), is highly required for the design of efficient electrocatalysts toward further energy conversion technologies. Here, we aim toward single-atom Au supported on NiFe LDH (^sAu/NiFe LDH) to clarify the activity origin of LDHs system and a 6-fold OER activity enhancement by 0.4 wt % ^sAu decoration. Combining with theoretical calculations, the active behavior of NiFe LDH results from the in situ generated NiFe oxyhydroxide from LDH during the OER process. With the presence of ^sAu, ^sAu/NiFe LDH possesses an overpotential of 0.21 V in contrast to the calculated result (0.18 V). We ascribe the excellent OER activity of ^sAu/NiFe LDH to the charge redistribution of active Fe as well as its surrounding atoms causing by the neighboring ^sAu on NiFe oxyhydroxide stabilized by interfacial CO₃^2- and H₂O interfacing with LDH.

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