Highly efficient water-splitting electrodes with stable operation at 3 A cm-2 in alkaline media through molecular linker assembly-induced all-in-one structured NiMo and NiFe electrocatalysts

Abstract

Developing nonnoble electrocatalyst-based water-splitting electrodes with high operational stability and low overpotentials is one of the most critical challenges in commercially available water-splitting reactions. In this study, we present water-splitting textile electrodes enabling remarkably low overpotentials and high stable operation. We first assembled conductive multi-walled-carbon-nanotubes (MWCNTs) with amine molecule-based linkers onto cotton textiles and subsequently electrodeposited Ni onto the MWCNT-incorporated textile. For the preparation of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrodes, NiMo and NiFe were further electrodeposited onto the Ni-electrodeposited textile electrode, respectively. These electrodes exhibited considerably low overpotentials in alkaline media (8 mV at 10 mA cm(-2) for HER and 189 mV at 50 mA cm(-2) for OER). Furthermore, the full-cell electrodes preserved a low cell voltage of 2.01 V at an unprecedentedly high current density of 3000 mA cm(-2) for a prolonged duration (> at least 1000 h).