Synthesis and investigation of bis(phenyl)fluorene and carbazole appended dipodal Schiff base for fluorescence sensing towards Sn(II) ion and its regioselective polymerization
Yükleniyor...
Dosyalar
Tarih
2023
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Science Sa
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
One-pot condensation reaction between 9,9-Bis(4-aminophenyl)fluorene and 9-Ethyl-9H-carbazole-3-carbalde-hyde afforded a chemosensor ((N,N ')-4,4 '-(9H-fluorene-9,9-diyl)bis(N-((9-ethyl-9H-carbazol-2-yl)methylene) aniline, SB) having Schiff base skeleton. The further step was the synthesis of the polymer (P-SB) via oxidative polycondesation reaction of SB. FT-IR, H-1 NMR and C-13 NMR instruments were used to characterize the func-tional groups on the monomer and polymer. Thermal stability and electrochemical features of SB and P-SB were characterized by thermogravimetric analysis-differential thermal analyses (TG-DTA) and cyclic voltammetry (CV), respectively. The glass transition and surface image of P-SB were determined from DSC and SEM mea-surements, respectively. UV-vis and photoluminescence spectroscopy (PL) allowed to determine the optical properties of SB and P-SB. The obtained polymer, which had the weight average molecular weight of 8400 Da identified by gel permeation chromatography (GPC), exhibited fluorescence property. The synthesized turn-on fluorogenic chemosensor SB showed high selectivity and sensitivity towards Sn2+ among the cations of Ag+, K+, Hg2+, Mn2+, Cd2+, Sn2+, Ca2+, Pb2+, Zn2+, Co2+, Ni2+, Cu2+, Fe3+, Al3+, Cr3+ and Cr6+. The fluorescence turn-on recognition process for the detection of Sn2+ was related to the restriction of C=N isomerization, fol-lowed by inhibiting intramolecular charge transfer (ICT), with consequent chelation-enhanced fluorescence (CHEF) mechanism. The stoichiometry ratio of the analyte-sensor adduct in the solution was found to be 1:1 by Job's plot method concomitant with a dramatic increase in fluorescent signal at 471 nm and a marked color change from colorless to turquoise blue upon addition of Sn2+ ions. Limit of detection value for the formation of SB-Sn2+ chelation was calculated as 3.37 nM. No change in PL intensity of SB-Sn2+ chelation was observed in the company of other metal ions. Reversibility of the chemosensor in its binding towards Sn2+ was demonstrated in the presence of chelating agent EDTA. The synthesized SB could effectively detect Sn2+ ion as a fluorescent sensor.
Açıklama
Anahtar Kelimeler
Schiff base, Oxidative polycondensation, Fluorescent chemosensor, CHEF, Sn2+, Benesi-Hildebrand
Kaynak
Journal of Photochemistry and Photobiology A-Chemistry
WoS Q Değeri
Q2
Scopus Q Değeri
Q1
Cilt
441
