Efficient Hydrogen Production Coupled with Polylactic Acid Plastic Electro Treatment over a CoFe LDH/MoSe₂/Ni_<i>x</i>Se_<i>y</i>/NF Heterostructure Electrocatalyst

The integration of oxidation reactions of small-molecule organic compounds such as urea and plastic with hydrogen evolution reactions (HER) forms a hot topic within the electrocatalytic field, facilitating energy-saving hydrogen production while degrading waste plastic pollutants. Here, a dual-functional electrocatalytic material, namely, graded CoFe LDH/MoSe2/NixSey/NF, was produced through a two-step successive hydrothermal approach. This constructed n-n/Schottky CoFe LDH/MoSe2/NixSey/NF heterojunction forms an internal electric field to optimize electron transfer pathways and provide abundant active sites, thus possessing superior electrocatalytic performance. A CoFe LDH/MoSe2/NixSey/NF catalyst exhibits a remarkable electrocatalytic performance, where the overpotential of HER is 88 mV at 10 mA cm–2, the oxygen evolution reaction stands at 1.510 V vs RHE, the oxidation reaction in electrolytes containing urea is at 1.391 V vs RHE, and lactate is at 1.371 V vs RHE at 50 mA cm–2. In full water splitting devices, the CoFe LDH/MoSe2/NixSey/NF electrocatalyst delivers the superior electrocatalytic performance in electrolytes containing urea, lactate. Meanwhile, the CoFe LDH/MoSe2/NixSey/NF electrolysis cell can achieve stable and efficient output at industrial temperatures (50–80 °C), with a current density of 100 mA cm–2 at 1.558 V at 65 °C. Coupled with the lactate oxidation reaction, the full water splitting cell constructed by the CoFe LDH/MoSe2/NixSey/NF electrocatalyst exhibits a low voltage at 1.380 V at 10 mA cm–2. This work presents an alternative approach and strategy for the management of waste plastics and the generation of hydrogen through dual-functional water splitting.