In Situ Reconstruction of Ag-Doped Ni₂P Electrocatalyst for Hydrogen Evolution and Value-Added Acrylamide Conversion

Concurrent remediation of organic pollutants in wastewater and energy-efficient hydrogen production is a highly attractive yet challenging dual strategy. Acrylamide (AA), depolymerized from polyacrylamide under natural conditions such as UV radiation and elevated temperatures, causes severe environmental pollution. Herein, in situ reconstructed Ag-doped Ni₂P nanosheets on Ni foam (CV-Ag-Ni₂P/NF) are developed as a bifunctional catalyst. This catalyst exhibits high activity for the AA oxidation reaction (AOR) while enabling energy-efficient hydrogen evolution reaction (HER). After electrochemical operation, the initial zipper-like morphology transforms into spherical features with interspersed rod-like particles, providing a larger electrochemical surface area and more active sites. Particularly, a potential of 1.82 V delivers 100 mA cm^-2 in the two-electrode AOR system. Remarkably, 79.3% AA removal was achieved after 24 h at 50 mA cm^-2. Meanwhile, ethanol generated at the anode serves as a value-added product. Density functional theory (DFT) calculations reveal that Ag atoms are the active sites for AA degradation and ethanol formation, with favorable adsorption energies. We propose a plausible AOR catalytic mechanism and reveal the key roles of Ag and Ni in H* adsorption and reduction of AA dehydrogenation energy, which offers a promising way of coupling AOR with HER to reduce energy consumption while producing high-value products.