Covalent organic framework COF-1 as a robust electrochemical sensor for oxygen containing toxic gases in mining and industrial environments: A DFT study

The toxic gases released from mining and industrial processes pose significant risk occupational safety and environmental integrity. In this context, design of efficient sensing materials for effective monitoring and detection of such gases is of considerable interest. In the current study, density-functional theory calculations are employed to explore oxygen containing toxic gases (SO 3 , NO 2 , CO 2 , CO, and O 3 ) on COF-1. Interaction energy, QTAIM, EDD, NBO, and FMO studies all contributed to a thorough comprehension of the analytes@COF-1 complexation. NCI and QTAIM analyses have been employed for probing the non-covalent interactions. The present study shows that NO 2 @COF-1 system has exhibited the greatest charge transfer in the NBO analysis, while the CO 2 @COF-1 system has shown the lowest. The outcomes of NBO charge transfer have been further strengthened with EDD analysis. FMO study reflects that COF-1 is most sensitive to O 3 analyte as observed from a substantial decrease in the HOMO-LUMO energy gap i.e. 6.21 eV compared to bare COF-1 surface. All studied analytes have shown that the surface is more sensitive towards O 3 compared to other analytes.