N-doped hollow carbon nanospheres anchored Pd NPs for mild selective hydrodeoxygenation of bio-models

•N-doped hollow carbon nanospheres anchored Pd catalysts (Pd/HCAFR-X) were synthesized.•The ethylbenzene yield in acetophenone HDO was close to 99% under mild conditions.•Nitrogen doping regulates the degree of defects on the surface of the carrier.•Defects offer stable anchor points for Pd loading, increasing the active sites of the reaction.•N modulates the electron distribution and guarantees that Pd0 remains at a high level.