Engineering of nickel‐cobalt oxide nanostructures based on biomass material for high performance supercapacitor and catalytic water splitting

Summary The purpose of the present study is to report the synthesis of a porous composite constructed from chicken feathers (CF) and nickel and cobalt salts and its application as a new material for modification of positive electrode surface used in supercapacitor as well as hydrogen and oxygen evolution. In this regard, we used waste CF as a biomass precursor and nitrate salts of nickel and cobalt to synthesize a highly porous composite through a solvothermal reaction. After characterization of nanocomposite using different physical and electrochemical techniques, it was used in fabrication of an electrochemical supercapacitor as well as hydrogen and oxygen evolution. The composite demonstrated remarkable electrochemical properties such as fast electrochemical reactions, high conductivity, and high reversibility. In addition, the prepared nanocomposite showed high‐specific capacitance of 2000 F g−1 (with current density of 0.5 mA cm−2 or 1 A g−1) as a supercapacitor. It also shows high energy density about 280 Wh kg−1 and high power density of 55 kW kg−1 as a positive electrode against an active carbon electrode in an asymmetric capacitor at potential range between 0 and 1.5 V. Moreover, the synthesized composite showed noticeable catalytic ability toward hydrogen evolution (HER) and oxygen evolution reaction (OER) with onset potentials of −0.03 and 1.48 V vs reversible hydrogen electrode, respectively. The OER performance of the resulting composite was better than standard platinum electrode. The optimal electrocatalyst (CFAC/Ni&Co oxides) revealed a current density of 10 mA cm−2 at the overpotentials of 87 mV for the HER and a current density of 20 mA at the overpotentials of 230 mV for OER, respectively. Moreover, it also showed a relatively low cell voltage (1.71 V) at a current density of 30 mA cm−2 for the overall water electrolysis. The purpose of the present study is to report the synthesis of a porous composite constructed from chicken feathers (CF) and nickel and cobalt salts and its application as a new material for modification of positive electrode surface used in supercapacitor as well as hydrogen and oxygen evolution.