Probing the impact of group 7 transition metals (TM: Mn, Tc, Re) encapsulated Ge-doped graphitic carbon nitrides (TM_Ge@g-C3N4) nanostructure as sensors for fenitrothion; an organophosphate insecticide

Abstract

The prevalence and detrimental effect of insecticides on the environment and human health highlights the necessity for developing effective sensing and adsorbing materials. Among these, organophosphate insecticides have garnered significant attention due to their widespread use, and potential adverse effects. Herein, the electronic properties of graphitic carbon nitride (g-C3N4) were engineered by doping with Ge-atom (Ge@C3N4) which was further enhanced by encapsulating the surface with manganese (Mn), technetium (Tc), and rhenium (Re) atom using density functional theory (DFT) at the GD3BJ-B3LYP/def2svp level of theory. The obtained results unveiled that the incorporation of Mn, Tc, and Re metals into the Ge@C3N4 framework significantly altered the electronic structure of the composite materials and enhanced the adsorption of Fenitrothion (FTT). After interaction of fenitrothion unto the engineered surfaces, a decrease in the energy gap was observed following a trends; Mn_Ge@C3N4 > Re_Ge@C3N4 > Tc_Ge@C3N4 with their respective energy from 1.972 eV to 1.892 eV, 1.333 eV to 1.172 eV, and 1.129 eV to 1.094 eV. And, Ge@C3N4 demonstrating a slight increase in the energy gap delineating the effectiveness of the modified compounds in sensing and adsorbing FTT. Interestingly, the adsorption studies proved to be chemisorption with the observed energies following the pattern base on their sensing capabilities Ge@C3N4 < Mn< Tc< Re corresponding to the energies as thus: −1.533 eV, −1.602 eV, −1.622 eV, −1.653 eV depicting Rhenium-encapsulated Ge@C3N4 doped surface the more favorable for the adsorption of FTT molecule followed by technetium-encapsulated Ge@C3N4. It was further observed that all the mechanistic adsorption studies and visual studies analyses presented Re_Ge@C3N4 as the most efficient surface for adsorption and detection of FTT_.