Strategic heteroatom doping enhances the sensitivity of covalent organic frameworks for ciprofloxacin detection

Ciprofloxacin (CFN) water pollution from poor waste management poses serious ecological and public health risks. In this research, we investigated the adsorption capacity of covalent organic frameworks (COFs) doped with heteroatoms such as nitrogen, phosphorus, sulfur, and silicon to enhance their ability to adsorb CFN. Using density functional theory (DFT) with the ꞷB97XD/6-311G(d) level of theory. This study included structural analysis, electronic properties, spectral analysis, topological studies, and adsorption energy investigations to provide a comprehensive understanding of the COF-CFN interaction. The results revealed that the bare COF was strongly chemisorbed with CFN, with an adsorption energy of -1.088 eV. Conversely, doping COFs with nitrogen alone or in combination with sulfur and silicon significantly improved chemisorption, with adsorption energies of -1.116 eV (N-COF-CFN), -1.415 eV (N-COF-S-CFN), and − 1.687 eV (N-COF-Si-CFN). These findings suggest that specific heteroatom doping can significantly enhance the adsorption capacity of COF for CFN.