1：Experimental Design and Method Selection:

The study involved the synthesis of new ISs composed of a silica matrix covalently bonded to 1-butyl-3-propyl-imidazolium cations via the propyl chain. The positive charge of this pendant group was counterbalanced by [Eu(TTA)4]? ions. These novel ISs were embedded in PMMA to produce flexible luminescent materials with high transparency under solar irradiation.

2：Sample Selection and Data Sources:

The samples were designated as PMMA-Ln-X, where Ln= Nd, Eu, Tb or Yb and X=10, 20 refers to the concentration of X=10 wt%, 20 wt% (mIS-Ln/mPMMA).

3：List of Experimental Equipment and Materials:

The structure of the materials was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), attenuated total reflection (ATR)/Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), scanning (SEM) and transmission electron microscopy (TEM), polarized optical microscopy (POM), and optical microscopy.

4：Experimental Procedures and Operational Workflow:

The PMMA-Ln-X materials were deposited on the c-Si PV cells by drop-casting of 0.07 mL of PMMA-Ln-X. Then, the devices were left to dry in an atmosphere rich in dichloromethane at room temperature for 5 h.

5：07 mL of PMMA-Ln-X. Then, the devices were left to dry in an atmosphere rich in dichloromethane at room temperature for 5 h. Data Analysis Methods:

5. Data Analysis Methods: The optical characterization of the materials was performed by UV/visible absorption spectra, photoluminescence, and the absolute q values were measured. The experimental voltage-current (V-I) curves were determined by illuminating the top surface of PV-1 with mimic-AM1.5G illumination using a solar simulator.