A New Soluble Copper Phthalocyanine Derivative as a Smart Material

Abstract

Copper phthalocyanine (CuPc) and its derivatives are considered as candidate materials in many applications. Particularly, easy and sensitive film-forming ability, commercial availability, chemical stability, and ease in tailoring its molecular structure make CuPc a versatile material. On the other hand, main challenge that Pcs often exhibit is their poor solubility in organic solvents. In this sense, this work involves designing of new CuPc derivatives by introducing suitable substitutions to improve the solubility in organic solvents. Specifically, [2,9,16,23-tetra{(4,5-Diphenyl-1H-imidazole)-2-yl-thio}phthalocyaninato-copper(II)] (1) and [2,9,16,23-tetra{(4,5-Diphenyl-1-methyl-1H-imidazole)-2-yl-thio}phthalocyaninato-copper(II)] (2) were prepared. The results show that compound 1 is soluble in tetrahydrofuran (THF), dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), and compound 2 is soluble in chloroform, acetone, methanol, THF, DMF, and DMSO. Optical and spectroscopic properties of the synthesized compounds were also investigated, and it was determined that the energy bang gaps of compounds 1 and 2 are 1.70 eV and 1.56 eV, respectively. Strikingly, we demonstrate that compound 1 is exhibiting a rapid and reversible color change behavior upon altering pH in the entire pH spectrum. As it is known, materials that respond reversibly to chemical and/or physical stimuli in a controllable fashion are regarded as smart materials. Hence, we report that compound 1 is actually a smart material that can be used as a simple yet efficient pH sensor.

Keywords

• Phthalocyanine
• Copper
• pH sensor
• Aggregation
• Band gap

References

1. Afify HA, Gadallah AS, El-Nahass MM, Atta Khedr M. 2015. Effect of thermal annealing on the structural and optical properties of spin coated copper phthalocyanine thin films. J Mol Struct, 1098: 161-166.
2. Ai X, Lin J, Chang Y, Zhou L, Zhang X, Qin G. 2018. Phase modification of copper phthalocyanine semiconductor by converting powder to thin film. Appl Surf Sci, 428: 788-792.
3. Alosabi AQ, Al-Muntaser AA, El-Nahass MM, Oraby AH. 2022. Structural, optical and DFT studies of disodium phthalocyanine thin films for optoelectronic devices applications. Opt Laser Technol, 155: 108372-108381.
4. Armarego WLF, Chai CLL. 2003. Purification of Laboratory Chemicals. 5 third ed.; Butterworth/Heinemann, Tokyo.
5. Chaure NB, Cammidge AN, Chambrier I, Cook MJ, Cain MG, Murphy CE, Pal C, Ray AK. 2011. High-mobility solution-processed copper phthalocyanine-based organic field-effect transistors. Sci Technol Adv Mater, 12(2): 025001.
6. Cherian RC, Menon CS. 2008. Preparation and characterization of thermally evaporated titanium phthalocyanine dichloride thin films. J Phys Chem, 69: 2858-2863.
7. Claessens CG, Blau WJ, Cook M, Hanack M, Nolte RJM, Torres T, Wohrle D. 2001. Phthalocyanines and Phthalocyanine Analogues: The Quest for Applicable Optical Properties. Monatsh Chem, 132: 3-11.
8. Dakoğlu-Gülmez A, Polyakov MS, Volchek VV, Tuncel-Kostakoğlu S, Esenpinar AA, Basova TV, Durmuş M, Gürek AG, Ahsen V, Banimuslem HA, Hassan AK. 2017. Tetrasubstituted copper phthalocyanine: Correlation between liquidcrystalline properties, films alignment and sensing properties. Sens Actuators B Chem, 241: 364-375.

9. Djurisic AB, Kwong CY, Lau TW, Guo WL, Li EH, Liu ZT, Kwok HS, Lam LSM, Chan WK. 2002. Optical properties of copper phthalocyanine. Opt Commun, 205: 155-162.
10. El Nhass MM, Sollman BS, Metwally BS, Farid AM, Farag AAM, El Shazly AA. 2001. Optical properties of evaporated iron phthalocyanine (FePc) thin films. J Opt, 30: 121-129.
11. Farag AAM. 2007. Optical absorption studies of copper phthalocyanine thin films. Opt Laser Technol, 39: 728-732.
12. Hamam KJ, Alomari MI. 2017. A study of the optical band gap of zinc phthalocyanine nanoparticles using UV-Vis spectroscopy and DFT function. Appl Nanosci, 7: 261-268.
13. He N, Chen Y, Doyle J, Liu Y, Blau WJ. 2008. Optical and nonlinear optical properties of an octasubstituted liquid crystalline copper phthalocyanine. Dyes Pigm, 76: 569-573.
14. Kim HJ, Kim JW, Lee HH, Lee B, Kim JJ. 2012. Initial growth mode, nanostructure, and molecular stacking of a ZnPc:C60 bulk heterojunction. Adv Funct Mater, 22: 4244-4248.
15. Mali SS, Dalavi DS, Bhosale PN, Betty CA, Chauhan AK, Patil PS. 2012. Electro-optical properties of copper phthalocyanines (CuPc) vacuum deposited thin films. RSC Adv, 2: 2100-2104.
16. McAfee T, Hoffman BC, You X, Atkin JM, Ade H, Dougherty DB. 2016. Morphological, Optical, and Electronic Consequences of Coexisting Crystal Orientations in β‑Copper Phthalocyanine Thin Films. J Phys Chem C, 120: 18616-18621.
17. Mobtakeri S, Akaltun Y, Özer A, Kılıç M, Tüzemen EŞ, Gür E. 2021. Gallium oxide films deposition by RF magnetron sputtering; a detailed analysis on the effects of deposition pressure and sputtering power and annealing. Ceram Int, 47: 1721-1727.
18. Nyokong T. 2007. Effects of substituents on the photochemical and photophysical properties of main group metal phthalocyanines. Coord Chem Rev, 251: 1707-1722.
19. Nyokong T. 2010. Electronic spectral and electrochemical behavior of near infrared absorbing metallophthalocyanines. Struct Bond, 135: 45-88.
20. Polat O, Caglar M, Coskun FM, Sobola D, Konecny M, Coskun M, Caglar Y, Turut A. 2020. Examination of optical properties of YbFeO3 films via doping transition element osmium. Opt Mater, 105: 109911.
21. Raval HN, Sutar DS, Rao VR. 2013. Copper(II) phthalocyanine based organic electronic devices for ionizing radiation dosimetry applications. Org Electron, 14(5): 1281-1290.
22. Sánchez-Vergara ME, Alonso-Huitron JC, Rodriguez-Gómez A, Reider-Burstin JN. 2012. Determination of the Optical GAP in Thin Films of Amorphous Dilithium Phthalocyanine Using the Tauc and Cody Models. Molecules, 17: 10000-10013.
23. Tong WY, Djurišić AB, Ng AMC, Chan WK. 2007. Synthesis and properties of copper phthalocyanine nanowires. Thin Solid Films, 515: 5270-5274.
24. van Leeuwen M, Beeby A, Fernandes I, Ashworth SH. 2014. The photochemistry and photophysics of a series of alpha octa(alkyl-substituted) silicon, zinc and palladium phthalocyanines. Photochem Photobio Sci, 13: 62-69.
25. Wang Y, Liu X, Shan H, Chen Q, Liu T, Sun X, Ma D, Zhang Z, Xu J, Xu Z-J. 2017. Tetra-alkyl-substituted copper (II) phthalocyanines as dopant-free hole-transport layers for planar perovskite solar cells with enhanced open circuit voltage and stability. Dyes Pigm, 139: 619-626.
26. Yabaş E, Erden F. 2023. Water-Soluble Quaternized Serotonin Substituted Zinc-Phthalocyanine for Photodynamic Therapy Applications. Cumhuriyet Sci J, 44(1): 99-105.
27. Yabaş E, Sülü M, Dumludağ F, Salih B, Bekaroğlu Ö. 2018. Imidazole octasubstituted novel mono and double-decker phthalocyanines: Synthesis, characterization, electrical and gas sensing properties. Polyhedron, 153: 51-63.
28. Yabaş E, Sülü M, Saydam S, Dumludağ F, Salih B, Bekaroğlu Ö. 2011. Synthesis, characterization and investigation of electrical and electrochemical properties of imidazole substituted phthalocyanines. Inorganica Chim Acta, 1(365): 340-348.
29. Yabaş E, Şenadim-Tuzemen E, Kaya S, Maslov MM, Erden F. 2023. Incorporation of graphene oxide to metal-free phthalocyanine through hydrogen bonding for optoelectronic applications: An experimental and computational study. J Phys Org Chem, e4496.
30. Yabaş E. 2023. The new soluble tetra-substituted oxo-titanium phthalocyanines: Synthesis, characterization, spectral and colorimetric pH sensing properties. J Mol Struct, 1284: 135435-135443.
31. Yu ZL, Ma QR, Liu B, Zhao YQ, Wang LZ, Zhou H, Cai MQ. 2017. Oriented tuning the photovoltaic properties of γ-RbGeX3 by strain-induced electron effective mass mutation. J Phys D, 50: 465101.