Highly dispersed Fe-doped CoP nanoparticles encapsulated with P, N co-doped hollow carbon shell toward robust bifunctional oxygen electrocatalysis and rechargeable Li-O2 batteries

Engineering morphology and doping heteroatom are regarded as effective strategies for boosting the electrocatalytic performances of the transition-metal phosphides (TMPs). Herein, an efficient bifunctional electrocatalyst, the hollow core-shell nanostructured Fe–CoP@DPA composite consisting of Fe–CoP nanoparticles confined in a dopamine-derived carbon shell was synthesized through a one-step direct phosphorization method. With the merits of the unique hollow structure and efficient synergistic catalytic effect, the Fe–CoP@DPA delivers superior bifunctional ORR/OER activity. Density functional theory (DFT) calculation illustrates that Fe doping can upshift the d-band center of Fe–CoP@DPA, thereby enhancing the adsorption of intermediates during catalysis. The Li–O₂ batteries with well-designed Fe–CoP@DPA cathode display an excellent long cycling stability of 282 cycles with a fixed capacity of 500 mAh g⁻¹ at 200 mA g⁻¹ and a high discharge specific capacity of 18208.5 mAh g⁻¹ at 100 mA g⁻¹. Rational designing the hollow nanostructured electrocatalyst with heteroatom doping will inspire the development of advanced cathode in Li–O₂ batteries.