1：Experimental Design and Method Selection:

The study involved synthesizing core-shell composites using a silane coupling agent method and core-shell-shell composites via a sol-gel chemical route. The design aimed to enhance luminescence and stability by coating silica shells.

2：Sample Selection and Data Sources:

Samples included SiO2 cores, PMDA-Si ligand, terbium perchlorate, and phenanthroline. Data were obtained from synthesized composites and characterized using various techniques.

3：List of Experimental Equipment and Materials:

Equipment included NMR spectrometer, SEM, TEM, XPS, TGA, FT-IR, XRD, photoluminescence spectrometer. Materials included Tb4O7, ammonia, CTAB, APTES, PMDA, phen, TEOS, ethanol, acetone, benzene.

4：Experimental Procedures and Operational Workflow:

Synthesis steps involved preparation of PMDA-Si, SiO2 cores, core-shell composites (SiO2@PMDA-Si-Tb and SiO2@PMDA-Si-Tb-phen), and core-shell-shell composites (SiO2@PMDA-Si-Tb@SiO2 and SiO2@PMDA-Si-Tb-phen@SiO2) using specific mass ratios, temperatures, and stirring times. Characterization was performed using the listed equipment.

5：Data Analysis Methods:

Data were analyzed using biexponential fitting for lifetime, spectral analysis for luminescence, and various spectroscopic and microscopic techniques for structural and compositional analysis.