TY - JOUR

T1 - Tetrasubstituted copper phthalocyanines

T2 - Correlation between liquid crystalline properties, films alignment and sensing properties

AU - Gülmez, Asuman Dakoğlu

AU - Polyakov, Maxim S.

AU - Volchek, Victoria V.

AU - Kostakoğlu, Sinem Tuncel

AU - Esenpinar, Aliye Aslı

AU - Basova, Tamara V.

AU - Durmuş, Mahmut

AU - Gürek, Ayşe Gül

AU - Ahsen, Vefa

AU - Banimuslem, Hikmat Adnan

AU - Hassan, Aseel K.

N1 - Publisher Copyright: © 2016 Elsevier B.V.

PY - 2017/3/31

Y1 - 2017/3/31

N2 - Copper phthalocyanines (CuPc) containing alkylthio (-S(CH2)nCH3, n = 7 and 15), alkyloxy- (-O(CH2)nCH3, n = 7 and 15) and polyoxo [-O(CH2CH2O)3CH3 and −S(CH2CH2O)3CH3] substituents were synthesized and investigated to reveal the effects of substituents type (alkylthio, alkyloxy and polyoxo) and the type of the connecting heteroatom (oxygen or sulphur) on the mesogenic properties, films alignment and sensing behaviour. The liquid crystalline properties of these phthalocyanines were investigated by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction techniques. The structure and morphology of spun thin films of copper phthalocyanine derivatives were studied by the UV–vis and Raman spectroscopies as well atomic force microscopy. The sensing properties of CuPc films were studied by the measurement of conductivity change upon interaction with ammonia in the range 10–50 ppm. All investigated films of CuPc derivatives display thermotropic columnar mesomorphism. It was shown that the films with polyoxo- [-O(CH2CH2O)3CH3 and −S(CH2CH2O)3CH3] substituents as well as with alkylthio −S(CH2)nCH3 (n = 7) substituents, which are liquid crystalline at room temperature, form ordered films with a random planar alignment of columns. Their films exhibit the better sensor performance with the maximal sensor response for the films of CuPc containing (-S(CH2CH2O)3CH3) substituents.

AB - Copper phthalocyanines (CuPc) containing alkylthio (-S(CH2)nCH3, n = 7 and 15), alkyloxy- (-O(CH2)nCH3, n = 7 and 15) and polyoxo [-O(CH2CH2O)3CH3 and −S(CH2CH2O)3CH3] substituents were synthesized and investigated to reveal the effects of substituents type (alkylthio, alkyloxy and polyoxo) and the type of the connecting heteroatom (oxygen or sulphur) on the mesogenic properties, films alignment and sensing behaviour. The liquid crystalline properties of these phthalocyanines were investigated by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction techniques. The structure and morphology of spun thin films of copper phthalocyanine derivatives were studied by the UV–vis and Raman spectroscopies as well atomic force microscopy. The sensing properties of CuPc films were studied by the measurement of conductivity change upon interaction with ammonia in the range 10–50 ppm. All investigated films of CuPc derivatives display thermotropic columnar mesomorphism. It was shown that the films with polyoxo- [-O(CH2CH2O)3CH3 and −S(CH2CH2O)3CH3] substituents as well as with alkylthio −S(CH2)nCH3 (n = 7) substituents, which are liquid crystalline at room temperature, form ordered films with a random planar alignment of columns. Their films exhibit the better sensor performance with the maximal sensor response for the films of CuPc containing (-S(CH2CH2O)3CH3) substituents.

KW - Ammonia sensors

KW - Chemical sensors

KW - Copper phthalocyanines

KW - Film alignment

KW - Liquid crystals

KW - THIN-FILMS

KW - OPTICAL-DETECTION

KW - ELECTROCHEMICAL PROPERTIES

KW - CHEMICAL SENSORS

KW - TRANSITION-METAL COMPLEXES

KW - MESOMORPHIC PROPERTIES

KW - LANGMUIR-BLODGETT-FILMS

KW - CARBON NANOTUBES

KW - ORIENTATION

KW - SUBSTITUTED PHTHALOCYANINES

UR - http://www.scopus.com/inward/record.url?scp=84992222090&partnerID=8YFLogxK

U2 - 10.1016/j.snb.2016.10.073

DO - 10.1016/j.snb.2016.10.073

M3 - Article

AN - SCOPUS:84992222090

VL - 241

SP - 364

EP - 375

JO - Sensors and Actuators, B: Chemical

JF - Sensors and Actuators, B: Chemical

SN - 0925-4005

ER -