Sensing of carbamazepine by AlN and BN nanoclusters in gas and solvent phases: DFT and TD-DFT calculation

Effects of Ge, Si, and B doping on the adsorption and detection properties of C60 fullerene towards methadone in gas and aqua phases: a DFT study

CONTEXT

Methadone can be abused and caused addictive and has various side effects. Therefore, the development of a fast and reliable diagnosis technique for its monitoring is essential. In this work, applications of C₆₀, GeC₅₉, SiC₅₉, and BC₅₉ fullerenes were investigated utilizing density functional theory (DFT) to find a suitable probe for methadone detection. The C₆₀ fullerene indicated weak adsorption energy for methadone sensing. Therefore, for the construction of the fullerene with good property for methadone adsorption and sensing, the GeC₅₉, SiC₅₉, and BC₅₉ fullerenes have been studied. The adsorption energy of GeC₅₉, SiC₅₉, and BC₅₉ in the most stable complexes were calculated at -2.08, -1.26, and -0.71 eV, respectively. Although GeC₅₉, SiC₅₉, and BC₅₉ all showed strong adsorption, only BC₅₉ present a high sensitivity for detection. Further, the BC₅₉ fullerene showing a proper short recovery time (about 1.11 × 10^-6 s for methadone desorption). Water as a solution is used to simulate the behavior of fullerenes in the body fluids, and results indicated that the selected pure and complex nanostructures are stable in water. The UV-vis spectrums indicated that the after adsorption of methadone on the BC₅₉ exhibits shift toward the lower wavelengths (blue shift). Therefore, our investigation indicated that the BC₅₉ fullerene is an excellent candidate for methadone detection.

METHODS

The interaction of methadone with pristine and doped C60 fullerenes surfaces was calculated using the density functional theory calculations. The GAMESS program and M06-2X method with a 6-31G(d) basis set were used for computations. Since the M06-2X method overestimates the LUMO-HOMO energy gaps (Eg) of carbon nanostructures, the HOMO and LUMO energies and Eg were investigated at the B3LYP/6-31G(d) level of theory using the optimization calculations. UV-vis spectra of excited species were obtained through the time-dependent density functional theory. To simulate the human biological fluid, the solvent phase was also evaluated in adsorption studies, and water was considered a liquid solvent.

Detection of Carbon, Sulfur, and Nitrogen Dioxide Pollutants with a 2D Ca12O12 Nanostructured Material

In recent times, nanomaterials have been applied for the detection and sensing of toxic gases in the environment owing to their large surface-to-volume ratio and efficiency. CO₂ is a toxic gas that is associated with causing global warming, while SO₂ and NO₂ are also characterized as nonbenign gases in the sense that when inhaled, they increase the rate of respiratory infections. Therefore, there is an explicit reason to develop efficient nanosensors for monitoring and sensing of these gases in the environment. Herein, we performed quantum chemical simulation on a Ca₁₂O₁₂ nanocage as an efficient nanosensor for sensing and monitoring of these gases (CO₂, SO₂, NO₂) by employing high-level density functional theory modeling at the B3LYP-GD3(BJ)/6-311+G(d,p) level of theory. The results obtained from our studies revealed that the adsorption of CO₂ and SO₂ on the Ca₁₂O₁₂ nanocage with adsorption energies of -2.01 and -5.85 eV, respectively, is chemisorption in nature, while that of NO₂ possessing an adsorption energy of -0.69 eV is related to physisorption. Moreover, frontier molecular orbital (FMO), global reactivity descriptors, and noncovalent interaction (NCI) analysis revealed that the adsorption of CO₂ and SO₂ on the Ca₁₂O₁₂ nanocage is stable adsorption, while that of NO₂ is unstable adsorption. Thus, we can infer that the Ca₁₂O₁₂ nanocage is more efficient as a nanosensor in sensing CO₂ and SO₂ gases than in sensing NO₂ gas.