Electrochemical oxidation of seawater using vanadium facilitated quaternary layered double hydroxides integrated with sulfur-doped carbon dots

Abstract

This research introduces a novel approach to electrocatalysis for sustainable energy generation, revealing the MnCoCrV LDH@SCDs composite supported by nickel foam (NF) as a high-performance catalyst specifically designed for seawater electrolysis. Constructed by incorporating sulfur-doped carbon dots (SCDs) into MnCoCrV layered double hydroxide (LDH) and depositing them onto a nickel foam substrate, this electrocatalyst demonstrates exceptional efficiency in the oxygen evolution reaction (OER) under alkaline seawater conditions. MnCoCrV LDH@SCDs/NF attains a noteworthy current density of 10 mA/cm² with a minimal overpotential of 209.4 mV. Additionally, it demonstrates a reduced Tafel value of 81.5 mV/dec, indicating faster kinetics. The electrode maintains impressive long-term stability, sustaining efficiency for approximately 50 h at a constant current density of 10 mA/cm². The increased surface area and reduced charge transfer resistance contribute to substantial electrocatalytic performance in seawater. This performance is primarily attributed to improved conductivity, resulting from synergistic contributions from high-valence-state vanadium ions and electrochemically active functional groups in SCDs. The MnCoCrV LDH@SCDs/NF electrocatalyst stands out for its intricate features that not only promote efficient electron transfer but also effectively counteract interference from chloride anions in seawater electrolysis. This study underscores the innovative nature of MnCoCrV LDH@SCDs/NF as a pivotal development in electrocatalyst research, offering a promising avenue for harnessing renewable energy from seawater.