Chalcone appended Organosilanes and their silica nanoparticles based UV-vis and fluorometric probes for Co2+ ions detection

Herein, we have designed heterocycle-based ligands having chalcone appended triazole silane in the scaffold by using a cost-effective and simple synthetic procedure. They were well characterized by using various spectroscopic techniques. In addition, organosilane was incapacitated on a silica nanosphere, and the resulting hybrid nanoparticles were thoroughly investigated using XRD, EDX, TGA, and SEM. Further, a recognition study of synthesized compounds was done by treating with different metal ions like Zn2+, Ni2+, Na+, Mg2+, K+, Ba2+, Ca2+, Ag+, Al3+ and Co2+ and it was observed in UV-Vis and fluorometric spectroscopy that ligand only shows selectivity and sensitivity towards Co2+ metal ions. Job's plot confirms the binding of a ligand with the metal ion in 1:1 stoichiometry. From the B-H plot association constant for hybrid silica nanoparticles was 6.3 x 10(4) M-1. In the emission spectra for both organosilane and H-NP's turn-off fluorescence behaviour was observed with detection limit value of 5.94 x 10(-) (7) M and 6.06 x 10(-8) M respectively. Moreover, by using Tauc's plot band gap energy of the ligand and functionalized nanoparticles were calculated. In addition, DFT calculations were done to provide valuable information about the ligand interaction with Co2+ metal ions.