1：Experimental Design and Method Selection:

The study uses an anodic aluminum oxide (AAO) template-guided approach for fabricating Ni superlattice photonic crystals (SPhCs). This involves structural replication from AAO templates with two arrays of nanopores, leveraging periodic anodization electric fields for self-alignment and sequential pore-opening for independent control of geometrical parameters.

2：Sample Selection and Data Sources:

Nickel (Ni) is selected as the active material. AAO templates are prepared using Al foils patterned with nanodent arrays via nanoimprinting with Ni moulds.

3：List of Experimental Equipment and Materials:

Equipment includes scanning electron microscope (SEM) for characterization, anodization setups with specific electrolytes, physical vapor deposition (PVD) for metal coating, electrochemical deposition systems, UV-vis-NIR spectrometer for optical measurements, solar simulator for energy applications, and simulation software (FDTD Solutions, COMSOL). Materials include Al foils, phosphoric acid, ethylene glycol, citric acid, sodium hydroxide, titanium dioxide, gold, titanium, polymethyl methacrylate, nickel sulfate, nickel chloride, boric acid.

4：Experimental Procedures and Operational Workflow:

The fabrication process involves: surface patterning of Al foils using Ni moulds, anodization to form nanopores, coating with protective layers, milling to open additional pores, wet-chemical etching to tune sizes and morphologies, metal evaporation, polymer support application, removal of Al and AAO, electrochemical deposition of Ni, and dissolution of polymer. Optical and energy conversion experiments are conducted with calibrated equipment.

5：Data Analysis Methods:

Data analysis includes SEM imaging for structural characterization, UV-vis-NIR spectroscopy for absorption measurements, FDTD simulations for electric field distributions, COMSOL simulations for electric field analysis during anodization, and efficiency calculations for solar applications using defined equations.