Synthesis and structural characterization of new complexes based on silver nanoparticles, diphenylcarbazide, and cetyltrimethylammonium bromide

In this work, the synthesis of new complexes based on silver nanoparticles (AgNP), diphenylcarbazide reagent (DPC), and cetyltrimethylammonium bromide (CTAB) was carried out, and the optimal conditions for their production were determined. The structures of the synthesized binary DPC+Ag and ternary DPC+Ag+CTAB complexes were studied using X-ray diffraction (XRD), infrared (IR), and ultraviolet (UV) spectroscopy. From the UV analysis, it was observed that the maximum peaks of the DPC reagent are found at wavelengths of 235 nm, 262 nm, 308 nm, and 345 nm, corresponding to the π-π* transition of the C-C bond and the n-π* transition between the C=N groups. Due to the surface plasmon resonance of the binary complex, new peaks in the absorption spectra were identified at wavelengths of 248 nm, 288 nm, 315 nm, and 355 nm. In the ternary complex, peaks in the absorption band were observed at wavelengths of 305 nm and 348 nm. The spectroscopic properties of DFC and its binary and ternary complexes were investigated through IR analyses. The aromatic C-H bonds of the phenyl group appear in the range of 3000-3100 cm⁻¹, while the C=C bonds of the phenyl group appear around 1500-1600 cm⁻¹. The peaks corresponding to the carbonyl (C=O) bond of the carbazide group are found in the range of 1650-1700 cm⁻¹, and the peaks related to the N-H groups appear around 1500-1600 cm⁻¹. The interaction of DFC with AgNPs was examined by analyzing shifts and changes in intensity of the IR spectroscopy absorption bands.