Controllable and facile preparation of Co9S8–Ni3S2 heterostructures embedded with N,S,O-tri-doped carbon for electrocatalytic oxidation of 5-hydroxymethylfurfural

Co 9 S 8 –Ni 3 S 2 @N,S,O-tri-doped carbon heterostructures, prepared by pyrolysis of the designed deep eutectic solvents, exhibited excellent electrooxidation performance of 5-hydroxymethylfurfural to produce 2,5-furandicarboxylic acid.