Title: | Cavitand-Decorated Silicon Columnar Nanostructures for the Surface Recognition of Volatile Nitroaromatic Compounds |
Author(s): | Tudisco C; Motta A; Barboza T; Massera C; Giuffrida AE; Pinalli R; Dalcanale E; Condorelli GG; |
Address: | "Dipartimento di Scienze Chimiche, Universita di Catania, and INSTM UdR Catania, V.le A. Doria 6, 95125 Catania, Italy. Dipartimento di Chimica, Universita degli Studi di Roma 'La Sapienza' and INSTM UdR Roma, P.le A. Moro 5, 00185 Roma, Italy. Dipartimento di Scienze Chimiche, della Vita e della Sostenibilita Ambientale, Universita di Parma and INSTM UdR Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy" |
ISSN/ISBN: | 2470-1343 (Electronic) 2470-1343 (Linking) |
Abstract: | "Nanocolumnar Si substrates (porous silicon (PSi)) have been functionalized with a quinoxaline-bridged (EtQxBox) cavitand in which the quinoxaline moieties are bonded to each other through four ethylendioxy bridges at the upper rim of the cavity. The receptor, which is known to selectively complex aromatic volatile organic compounds (VOCs) even in the presence of aliphatic compounds, has been covalently anchored to PSi. The larger surface area of PSi, compared to that of flat substrates, allowed one to study the recognition process of the surface-grafted receptors through different techniques: Fourier-transform infrared spectroscopy, thermal desorption, and X-ray photoelectron spectroscopy. The experiments proved that surface-grafted cavitands retain the recognition capability toward aromatic VOCs. In addition, the affinities of EtQxBox for various aromatic compounds (i.e., benzene, toluene, nitrobenzene, and p-nitrotoluene) have been studied combining density functional theory computations and thermal desorption experiments. Computational data based on the crystal structures of the complexes indicate that this cavitand possesses a higher affinity toward aromatic nitro-compounds compared to benzene and toluene, making this receptor of particular interest for the detection of explosive taggants. The results of computational studies have been validated also for the surface-grafted receptor through competitive recognition experiments. These experiments showed that EtQxBox-functionalized PSi can recognize nitrobenzene in the presence of a significant excess of aromatic vapors such as benzene (1:300) or toluene (1:100)" |
Notes: | "PubMed-not-MEDLINETudisco, Cristina Motta, Alessandro Barboza, Tahnie Massera, Chiara Giuffrida, Antonino E Pinalli, Roberta Dalcanale, Enrico Condorelli, Guglielmo G eng 2019/08/29 ACS Omega. 2018 Aug 15; 3(8):9172-9181. doi: 10.1021/acsomega.8b01018. eCollection 2018 Aug 31" |