Carbon nitride nanotube as a sensor for alkali and alkaline earth cations

• Published in: Applied surface science Vol. 264; pp. 699 - 706
• Main Authors: Beheshtian, Javad, Baei, Mohammad T., Bagheri, Zargham, Peyghan, Ali Ahmadi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-01-2013; Elsevier
• Subjects: Adsorption; Band gap; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; DFT; Exact sciences and technology; Nanostructures; Physics; DFT; Nanostructures; Band gap; Adsorption; Energy gap; Measurement sensor; Density functional method; Carbon nanotubes; Cations; Carbon nitrides
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2012.10.100

► Adsorption of alkali and alkaline earth cations on a CN nanotube studied by DFT. ► The alkaline cation adsorption may raise potential barrier of the electron emission. ► The tube may act as a sensor in the presence of alkali and alkaline cations.
Adsorption of several alkali (Li+, Na+, and K+) and alkaline earth (Be2+, Mg2+, and Ca2+) cations on the surface of a zigzag (9, 0) carbon nitride nanotube has been investigated using density functional theory. It has been found that almost all of the cations prefer to be strongly chemisorbed at the center of porous site of the tube surface. The adsorption of alkaline cations much more influences the electronic properties of the tube, in comparison with the alkali ones, so that it is transformed from an intrinsic semiconductor with HOMO/LUMO energy gap of 4.02eV to extrinsic p-type one with the gap of 0.54–1.94eV. The alkaline cation adsorption may significantly raise potential barrier of the electron emission from the tube surface, hence impeding the field emission. It has been also concluded that the electrical sensitivity of the tube toward the cations may be in the order: Be2+≫Mg2+≫Ca2+≫Li+∼Na+∼K+.