Core-shell construction of metal@carbon by mechanochemically recycling plastic wastes: towards an efficient oxygen evolution reaction

Rational surface engineering of non-noble metal electrocatalysts supported on carbon materials (metal@C) provides potential opportunities to gain sustainable energy by electrocatalytic water splitting. Here, plastic waste-based electrode materials obtained by mechanochemical synthesis and in situ pyrolysis doping afford low overpotentials (?(10) = 263 mV, Tafel slope = 34 mV dec(-1)), superior durability, and operation simplification. The ball milling treatment promoted solid dispersion of metal precursors in plastics, further constructing a core-shell structure with tunable thickness to regulate the activity. The metal species were encapsulated by a plastic-derived carbon shell and uniformly embedded in a highly porous carbon support. By changing the metal precursor, alternative OER electrocatalysts based on transition metal (Co, Ni, Mn and Fe) sites @C could accelerate the oxygen evolution kinetics, and the OER activity trend was Ni > Co & AP; Fe > Mn, superior to most carbon-based OER electrocatalysts and commercial IrO2 used to date. The synergetic effect of the encapsulated metal and the high-curvature onion-like carbon shell plays a fundamental role in the superior OER catalytic performance. Furthermore, this method presents an approach for the efficient utilization and upward recycling of plastics as high-value electrode materials.

Automated summary

Rational surface engineering of non-noble metal electrocatalysts supported on carbon materials provides potential opportunities for sustainable energy by electrocatalytic water splitting. Plastic waste-based electrode materials obtained by mechanochemical synthesis and in situ pyrolysis doping offer low overpotentials, superior durability, and operation simplification. This method also presents an approach for the efficient utilization and upward recycling of plastics as high-value electrode materials.