Tuning of the gold work function by carborane films studied using density functional theory

0507908 - FZÚ 2020 RIV GB eng J - Článek v odborném periodiku
Hladik, Martin - Vetushka, Aliaksi - Fejfar, Antonín - Vázquez, Héctor
Tuning of the gold work function by carborane films studied using density functional theory.
Physical Chemistry Chemical Physics. Roč. 21, č. 11 (2019), s. 6178-6185. ISSN 1463-9076. E-ISSN 1463-9084
Grant CEP: GA TA ČR TH02020628; GA ČR(CZ) GJ17-27338Y; GA MŠMT EF16_019/0000760
Grant ostatní: OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institucionální podpora: RVO:68378271
Klíčová slova: density functional theory * SIESTA code * self-assembled monolayers * carborane * Au surface * work function
Obor OECD: Electrical and electronic engineering
Impakt faktor: 3.430, rok: 2019
Způsob publikování: Omezený přístup
https://doi.org/10.1039/c9cp00346k

Using density functional theory including van der Waals interactions, we calculate the adsorption and electronic properties of dithiol-dicarba-closo-dodecaboranes chemisorbed on Au(111) surfaces. Carborane molecules consist of a cage-like structure made of boron and carbon atoms and possess a large intrinsic dipole. We consider two functionalized carborane positional isomers, with thiol linker groups attached to either carbon or boron backbone atoms, such that when adsorbed on the Au substrate, the molecular dipole points towards the metal surface or away from it. We investigate a large number of junction geometries and find that carborane adsorption can induce significant changes in the work function of the Au substrate, in the range of 1 eV. These changes depend strongly on the interface geometry at the atomistic level. From the analysis of these junction structures, we provide a picture of the driving mechanisms that determine adsorption geometries, and relate them to interface electronic structure and resulting work function modification. In particular, our results highlight the important role played in these interface quantities by distortions in the Au surface layer induced by carborane adsorption.
Trvalý link: http://hdl.handle.net/11104/0298872