1：Experimental Design and Method Selection:

The study involved the synthesis of CsPbBr3 PeQDs and RGO nanosheets composites through an in-situ solution reaction. The effect of RGO amount on the photoluminescence of PeQDs was investigated.

2：Sample Selection and Data Sources:

CsPbBr3 QDs without or with RGO sheets were prepared under the same conditions. Different doses of graphene solution were used to vary the RGO content.

3：List of Experimental Equipment and Materials:

Equipment included an X-ray diffractometer (Bruker D8 Advance), transmission electron microscopy (JEM-2100 plus, JEOL, Japan), UV–vis spectrophotometer (PE Lambda 950), spectrofluorometer (Fluorolog-3 Horiba Jobin Yvon), and variable angle spectroscopic ellipsometers (VASE, J. A. Woollam Co.). Materials included Cs2CO3, octadecene (ODE), oleic acid (OA), PbBr2, oleylamine (OAm), and graphene solution.

4：Experimental Procedures and Operational Workflow:

The synthesis involved drying PbBr2 in ODE, injecting OAm and OA along with different doses of graphene solution, raising the temperature, injecting Cs-oleate solution, cooling, and centrifugation. Characterization included XRD, TEM, UV-vis absorption, PL spectra, PL decay curves, and ellipsometry measurements.

5：Data Analysis Methods:

PL decay dynamics were analyzed using tri-exponential decay function. Ellipsometric data were fitted using WVASE 32 software. Numerical simulations were performed using the finite difference time domain (FDTD) method.