N-doping induced tensile-strained Pt nanoparticles ensuring an excellent durability of the oxygen reduction reaction

•The surfactant- and polymer-free synthesis of a new kind of nonmetallic N-doped Pt nanoparticles.•The N doping within Pt lattice induces tensile strain, leading to an enhanced ORR activity and excellent durability.•This N-doped Pt nanocatalyst shows a negligible degradation in ORR activity (only 3.7%) after a 20,000-cycle ADT.•Provide a competitive strategy for preparation of Pt-based oxygen reduction catalysts in PEMFCs.