Ru nanoparticles immobilized on self-supporting porphyrinic MOF/nickel foam electrode for efficient overall water splitting

Abstract

To achieve carbon neutrality, the development of effective and durable electrodes for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is of utmost importance. Herein, the Ru3.4-PMOF/NF electrode was successfully prepared by immobilizing Ru nanoparticles on porphyrinic metal-organic framework/nickel foam (PMOF/NF), effectively driving both the OER and the HER in an alkaline electrolyte. To achieve 10 mA cm−2, the Ru3.4-PMOF/NF electrode only required overpotentials of 19 and 215 mV for HER and OER, respectively. For overall water splitting, an ultra-low cell voltage of 1.468 V was required to drive 10 mA cm−2, surpassing the performance of the integrated Pt/C and RuO2 couple electrode (1.6627 V). The outperformed electrocatalytic activity could be ascribed to the well-dispersed Ru nanoparticles, the self-reconstruction of PMOF, the synergistic effect, and the lamellar morphology. This study offers a promising approach for the development of ruthenium-doped electrodes that can enhance the efficiency of electrocatalytic water splitting.