1：Experimental Design and Method Selection:

The study used an electrospinning method combined with calcination to synthesize Mg-doped perovskite LaNiO3 nanofibers (LNMO NFs) and pristine LaNiO3 nanofibers (LNO NFs). DFT calculations were employed to understand the catalytic mechanisms.

2：Sample Selection and Data Sources:

Samples were synthesized using specific precursors (e.g., La(NO3)3·6H2O, Ni(Ac)2·4H2O, Mg(NO3)3·6H2O, PVP, DMF). Electrochemical measurements were conducted in

3：1M KOH electrolyte. List of Experimental Equipment and Materials:

Equipment included a PANalytical X'Pert powder diffractometer for XRD, Tecnai G2 F20 TEM, SU8020 FESEM, Quantachrome ASIQC0R100-3 analyzer for nitrogen sorption, STXM at Canadian Light Source for XANES, rotating disk electrode (RDE) setup, and VASP for DFT calculations. Materials included glassy-carbon electrodes, Nafion solution, Super P carbon, Pt/C and RuO2 catalysts, zinc foil, nickel foam, and polypropylene/polyethylene membrane.

4：Experimental Procedures and Operational Workflow:

Synthesis involved dissolving precursors in DMF, adding PVP, electrospinning with specific parameters (e.g., flow rate

5：2 mL h-1, voltage 20 kV), drying at 80°C, and calcining at 700°C. Characterization included XRD, SEM, TEM, XPS, nitrogen sorption, and STXM. Electrochemical tests involved preparing catalyst inks, dropping on electrodes, and measuring ORR and OER performance in a three-electrode cell. Zinc-air batteries were assembled and tested for discharge and cycling performance. Data Analysis Methods:

Data were analyzed using software like aXis2000 for STXM, and electrochemical data were iR-corrected. DFT calculations used the BEEF-vdW functional and DFT+U method.