Network-structured Ru/RuO 2 -FeNiCo-LDH as a high-performance bifunctional electrocatalyst for overall water splitting

Abstract Rationally designing and synthesizing efficient bifunctional electrocatalysts is crucial for overall water splitting (OWS). Herein, a Ru/RuO 2 -FeNiCo-LDH/NF electrocatalyst with an interconnected porous network was fabricated on nickel foam (NF) via electrodeposition followed by precursor combustion. At a current density of 10 mA cm − 2 , Ru/RuO 2 -Fe-0.1-Co-0.1-LDH/NF requires overpotentials of 52 mV and 205 mV in 1 M KOH for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. A two-electrode electrolyzer using Ru/RuO 2 -Fe-0.1-Co-0.1-LDH/NF as both electrodes requires a cell voltage of 1.40 V to reach a current density of 10 mA cm − 2 . The interconnected porous network, Ru/RuO 2 active species, low charge-transfer resistance ( R ct = 13.7 Ω), and large electrochemically active surface area (ECSA = 704.5 cm 2 ) synergistically contribute to efficient OWS. This work offers new insights into developing efficient bifunctional electrocatalysts for OWS.