The interaction between the CPB NCs and the ZIF-8 framework can alter the local dielectric environment around the nanocrystals, further contributing to the shift. Additionally, the CPB/ZIF-8 nanocomposite showed a significant reduction in PL intensity, quenching by 92% compared to pristine CPB NCs. This quenching effect can be attributed to charge transfer from the CPB to the ZIF-8 framework, as depicted in Scheme 3. The primary cause of this charge transfer is likely the interaction between Pb²⁺ ions in CPB and nitrogen atoms in the imidazole ligands of ZIF-8. . This observation aligns with the earlier FTIR results, which indicated ligand exchange.