Exploration of the adsorption of caffein molecule on the TiO2 nanostructures: A density functional theory study

Journal of Nanoanalysis

مقالات آماده انتشار، پذیرفته شده، انتشار آنلاین از تاریخ 26 تیر 1397

نوع مقاله: Original Research Paper

شناسه دیجیتال (DOI): 10.22034/jna.2018.561204.1072

نویسندگان

Amirali Abbasi^* ؛ Jaber Jahanbin Sardroodi

Azarbaijan Shahid Madani University

چکیده

First principles calculations were performed to study the adsorption behaviors of caffein molecule on the pristine and N-doped TiO2 anatase nanoparticles. Both oxygen and nitrogen in the caffein molecule can react with the TiO2 nanoparticle strongly. Thus, the binding sites were located on the oxygen or nitrogen atom of the caffein, while on the TiO2 nanoparticle the binding site occurs on the fivefold coordinated titanium atoms. By counting van der Waals (vdW) interactions, it was found that the adsorption on the N-doped TiO2 is more favorable in energy than the adsorption on the undoped one, indicating the high sensitivity of N-doped TiO2 nanoparticles towards caffein molecules. It means a dominant effect of nitrogen doping on the adsorption properties of pristine TiO2. The large overlaps in the PDOS spectra of the oxygen and nitrogen atoms of the caffein and titanium atom of TiO2 represent a forming Ti-O and Ti-N bonds between them. The molecular orbital calculation results indicate that the HOMOs are strongly localized on the caffein. Charge analysis based on Mulliken charges reveals a considerable charge transfer from the caffein to the TiO2 nanoparticle.

کلیدواژه‌ها

Caffein؛ Tio2 Nanoparticle؛ Electronic Properties؛ density functional theory