Environmental implications of SiBN nanoflakes in pharmaceutical pollutant detection and removal: insights from first-principle calculations.

Pharmaceutical pollutants, such as carbamazepine (CBZ), are emerging contaminants that pose significant environmental and health risks due to their persistence in aquatic ecosystems and incomplete removal by conventional wastewater treatments. This study leverages density functional theory (DFT), a gold-standard computational quantum mechanical modeling method, to evaluate the efficacy of SiBN nanoflakes-a novel two-dimensional material-for CBZ adsorption and detection. Our first-principles calculations reveal thermodynamically stable interactions between CBZ and SiBN, with adsorption energies of - 0.83 eV (edge) and - 0.82 eV (surface). The material's responsive optical behavior is quantified through time-dependent DFT, showing a 138 nm blueshift in UV-Vis spectra upon adsorption, a hallmark of its sensing capability. Furthermore, DFT-calculated charge transfer (0.04-0.06 e) and Fermi-level shifts (- 4.52 to - 4.69 eV) underscore SiBN's enhanced electronic properties, enabling selective pollutant detection. By bridging atomic-scale insights (bond distortions, orbital hybridization) with macroscale environmental applications, this work demonstrates how DFT-guided design unlocks SiBN's dual functionality as a scalable adsorbent and optical sensor. These findings provide a quantum-mechanical foundation for advancing SiBN nanoflakes as a scalable, stable, and effective material for addressing pharmaceutical pollutants in water, offering a sustainable alternative to conventional methods plagued by secondary contamination risks.