Electrochemical Reforming of Methanol using Multilayer Nanoarchitectonics with Ligand Exchange-Induced Layer-by-Layer Assembly toward Electrocatalytic Hydrogen Production

Electrochemical water splitting, essential for hydrogen production, faces challenges, particularly the oxygen evolution reaction (OER) at the anode, leading to increased overpotentials. To tackle these issues, electrochemical reforming has been explored as an innovative solution, wherein alternative organic molecules replace oxygen evolution at the anode. Herein, we report the development and characterization of 3D multilayer thin-film electrodes comprising Au nanoparticles (NPs) and the 4-(dimethylamino) pyridine (DMAP) ligand assembled through ligand exchange-induced layer-by-layer (LE-LbL) assembly for electrochemical hydrogen generation. The ligand exchange process involving DMAP facilitates a strong binding energy between the ligand and the surface of Au NPs, ensuring efficient LbL assembly. Our study not only demonstrates the fabrication of single-metal component LbL multilayer electrodes but also provides insights into both facile charge and mass transfer of multilayer electrodes. This understanding is crucial for designing high-performance electrocatalysts by enhancing the mass transfer pathway and charge transfer within the electrode without deterioration of electrocatalytic performance due to mass transfer restrictions. These LE-LbL-based multilayer electrodes present a promising model system for advancing the electrocatalytic efficiency of hydrogen production processes, contributing to the establishment of future sustainable and efficient energy solutions.