Degradation-resistant waste plastics derived carbon supported MoS2 electrocatalyst: high‒nitrogen dependent activity for hydrogen evolution reaction

It is still a great challenge to design a simple, low-cost and highly active catalyst for the industrial production of hydrogen from water electrolysis. Herein, we report a synthesis of molybdenum disulphide (MoS2) supported on carbon supports with high concentration of doped-nitrogen derived from large scale industrial waste plastics, i.e. melamine (CWM) and polyurethane (CWPU), by a simple hydrothermal reaction. Few layers of MoS2 nanosheets with high catalytic activity can be very-well dispersed on CWM and CWPU. The supports with high‒nitrogen content can not only greatly improve the conductivity of supported MoS2 nanosheets, but also provide additional active sites with the presence of high pyridinic‒N content. The synergistic effects between the MoS2 nanosheet and CWM and CWPU contribute to high hydrogen evolution reaction (HER) activity. As the concentration of doped-N increases, the HER performance of MoS2-based catalysts is improved. MoS2/CWM 1:1 with the highest nitrogen content (11.1 wt %) shows the lowest overpotential of 56 mV at 10 mA cm−2, the smallest Tafel slope of 36.6 mV·dec−1, and the highest exchange current density of 0.35 mA cm−2 in acidic condition, which are comparable to that of commercial 20% Pt/C.