These larger crystals are stabilized by the framework due to surface energy, ligand exchange, and electrostatic interactions. Structural analysis XRD XRD analysis was performed on ZIF-8, pristine CPB, and CPB/ZIF-8 to examine the formation of nanocomposites and their structural properties, as illustrated in (Figure ). The diffraction pattern of CPB and ZIF-8 (Figure , red and blue line, respectively) exhibits well-defined peaks corresponding with the previously reported crystalline structure (JCPDS -01-072-7929 and JCPDS -00-062-1030, respectively). Notably, due to the random orientation of CPB NCs, the typical shoulder peaks at 15.2º, 21.5º, and 30.5º are indistinguishable. Interestingly, the CPB/ZIF-8 nanocomposite exhibits only the characteristic ZIF-8 and CPB characteristic peaks for ZIF-8 and CPB. Indeed, The sharp, well-defined peaks of ZIF-8 remain intact without any noticeable broadening, confirming that its crystalline structure was preserved in the nanocomposite. The XRD results confirm the successful formation of the CPB/ZIF-8 nanocomposite, with both materials retaining their characteristic crystalline structures as evidenced by the sharp ZIF-8 peaks and distinct CPB reflections. exhibited a prominent peak at 420 cm⁻¹, corresponding to the stretching vibration of the Zn-N bond between Zn²⁺ and the 2-methylimidazole ligand. Pristine CPB displayed characteristic peaks at 2848 cm⁻¹ and 2917 cm⁻¹, representing its organic ligands' C-H bending and stretching vibrations. In the FTIR spectrum of the CPB/ZIF-8 nanocomposite, peaks corresponding to both ZIF-8 and CPB were observed. The ZIF-8 peaks exhibited significantly higher intensity than those of CPB, indicating a higher concentration of ZIF-8 per unit volume. Interestingly, the CPB ligand peaks in the 2850-2950 cm⁻¹ range showed a significant reduction in intensity, supporting ligand exchange alongside surface charge interactions. This reduction indicates interactions between Pb²⁺ ions from the CPB NCs and the nitrogen atoms of the imidazole ligands in ZIF-8, enabling both chemical and physical adsorption.