Synthesis of Ag@g-C₃N₄ coordination compound via Ag(NH₂COCN₂)₆NO₃ thermal decomposition and its activities in the catalytic reduction of nitrophenol compounds

The activities of silver (Ag) complexes of graphitic carbon nitride with different metal ratios in the catalytic reduction reaction of 4-nitrophenol to 4-nitroamine were investigated in this study. For this purpose, the compounds of urea: dicyanodiamine in a ratio of 3:7 and the Ag(NH2COCN2)6NO3 complex were reacted together in order to prepare Ag@g-C3N4 by thermal decomposition in a single step. The resulting products were analyzed by X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR), Field Emission Scanning Electron Microscope- Energy Dispersive X-ray spectroscopy (SEM-EDS), and High-Resolution Transmission Electron Microscope (HRTEM) and the binding properties of Ag in the structure were determined. AAS analysis was also used to determine the amount of silver. The catalytic activities of Ag@g-C3N4 were evaluated for the reduction of p-nitrophenol (PNP) to p-aminophenol (PAP) in the presence of excessive sodium borohydride (NaBH4) as a reducing agent by monitoring conversion at lambda 400 nm. The prepared Ag@ g-C3N4 nanocatalysts were observed to have very good catalytic activity in the range of 95.1-99.6 % in the catalytic reduction reaction in which PNP was used as a model and the catalyst: substrate ratio was studied at 1:5, 1:50 and 1:100. Especially with the leaching problem and the high activity of silver atoms directly added to the g-C3N4 structure with the new synthesis technique, a new material has been added to the literature.