3D metal dendrite-derived petaloid shaped NiFe2O4@ NFM as binderless electrode for oxygen evolution reaction and electrochemical energy storage

Abstract

Two-dimensional nanosheets materials anchored on the surface of ordered dendritic array substrate not only realizes the multiple scale assembly of materials, but also enables the construction of self-supporting electrodes. In this work, we fabricate the Ni–Fe alloy dendritic array matrix by the facile electrodeposition process for the first time. It can provide a large number of vertical paths for electrolyte ions, electron transfer and gas overflow, which further helps to improve the electrochemical performance of electrode. Whereafter, the metal on the surface of dendrite is converted into NiFe2O4 via in situ calcination oxidation method. The NiFe2O4@NiFe dendrite matrix electrode is characterized by Field emission scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy analysis. During the oxygen evolution reaction measurement, the as-prepared NiFe2O4@NFM-3 requires a low overpotential of 234 mV (vs.RHE) to arrive 10 mA cm−2 current density. Furthermore, the NiFe2O4@NFM-3 electrode reveals the high area capacitance about 1560 mF cm−2 at current density of 1 mA cm−2. The electrochemical performances test results demonstrate that this fiber electrode can serve as the bifunctional electrode in oxygen evolution reaction (OER) and energy storage.