Year: 2022
Type: article
Abstract: Surface modification of nanoparticulate TiO 2 and Al 2 O 3 materials with 4-fluorophenylboronic acid is investigated in order to both evaluate the novel surface modification schemes and develop spectroscopic labels for surface characterization. The chemistry of the modification is followed on all these surfaces using X-ray photoelectron spectroscopy, multinuclear ( 11 B, 19 F, and 13 C) solid-state and solution NMR, and infrared spectroscopy to determine the binding modes of this compound using boron and fluorine as probe atoms. Density functional theory model calculations are utilized to visualize predicted surface species and to interpret the results of spectroscopic measurements. A comparison is made among TiO 2 rutile, TiO 2 anatase, and γ-Al 2 O 3 . On all three materials, the modification proceeds via the boronic functional groups, with metal oxide-controlled surface chemistry. The bonding configuration depends on the material and is dominated by a monodentate species for titania and by bidentate species for alumina. The surface structures determined to form on all the oxide semiconductors investigated suggest that sensitization or monolayer doping approaches with a well-defined chemical interaction via a boronic functionality can be developed.
Source: Chemistry of Materials
Institutions: University of Delaware, Chemours (United States)
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: green
Funder: University of Delaware
OpenAlex ID: W4311376528