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    Asymmetric phthalocyanine-based hole-transporting materials: evaluating the role of heterocyclic units and PMMA additive
    (Royal Soc Chemistry, 2024) Dogan, Sifa; Unal, Muhittin; Demircioglu, Perihan Kubra; Molina, Desire; Ince, Mine; Akin, Seckin
    Two novel asymmetric phthalocyanine derivatives, ZnPc-1 and ZnPc-2, are synthesized to enhance charge transfer properties and mitigate deep-level traps on the perovskite surface using electron-rich nitrogen atoms. PSCs with ZnPc-1 and ZnPc-2 as hole-transporting materials (HTMs) achieved power conversion efficiencies (PCEs) of 12.11% and 8.98%, respectively. Incorporating a small amount of PMMA into the HTM solution significantly improved performance, resulting in PCEs of 16.2% and 12.5% for ZnPc-1 and ZnPc-2, respectively. The addition of PMMA enhances conductivity and prevents moisture intrusion, boosting both the efficiency and stability of PSCs. ZnPcs with pyridine or imidazole units were synthesized as HTMs in PSCs. PMMA addition improved performance and stability, reaching 16.2% PCE for ZnPc-1.
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    Beyond the Conventional Photodynamic Therapy by Water-Soluble Phthalocyanines
    (Wiley-V C H Verlag Gmbh, 2022) Yuzer, Lecturer Abdulcelil; Demircioglu, Perihan Kubra; Yetkin, Lecturer Derya; Ince, Mine; Ayaz, Furkan
    Compared to the classical chemotherapy applications, PDT applications are based on a non-toxic compound that can be specifically activated by shining a certain wavelength of light. Constitituvely active chemotherapy drug agents lead to detrimental and unwanted side effects that halt the normal life standards of the cancer patients. Localized and controlled activation of the drug agents by PDT applications aims to overcome the side effects associated with the treatment. In our study we synthesized a unique set of phthalocyanine molecules that are water soluble to make them biocompatible. Moreover, these compounds anti-cancer activities were measured from multiple angles. Anti-cancer PDT activities of the derivatives were studied by testing their effects on the cell proliferation, apoptosis and cell cycle progression. Moreover, these derivatives anti-metastatic, anti-angiogenic and immunomodulatory photodynamic activities were comprehensively studied by focusing on the intracellular signaling pathways that may play important roles in carcinogenesis, angiogenesis, metastasis and immune reactions. For the first time to our knowledge we are presenting data beyond the classical or canonical PDT applications in which generation of the reactive oxygen species (ROS) is explained as the main mechanism of the action for the PDT applications. Our results suggest that non-canonical PDT activity can be observed independent of the ROS generation efficiencies probably by affecting the intracellular signaling pathways. These novel set of phthalocyanine derivatives may find applications against colon, lung, breast and prostate cancer.
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    Cu(II) and Ni(II) Phthalocyanine-Based Hole-Transporting Materials for Stable Perovskite Solar Cells with Efficiencies Reaching 20.0%
    (Wiley-V C H Verlag Gmbh, 2024) Xia, Jianxing; Labella, Jorge; Demircioglu, Perihan Kubra; Perez-Escribano, Manuel; Calbo, Joaquin; Orti, Enrique; Ince, Mine
    Herein, Cu(II)Pcs and Ni(II)Pcs peripherally tetra-functionalized with 5-hexylthiophene (HT), 5-hexyl-2,2 '-bithiophene (HBT), and tertbutyl groups (TB) are readily synthesized and employed as hole-transporting materials (HTMs) in mixed-ion perovskite ([FAPbI3]0.85[MAPbBr3]0.15) solar cells, achieving power conversion efficiencies (PCEs) up to 20.0%. Remarkably, both the peripheral functionalization and the central metal are found to play a role in the performance. Through a combination of experimental and theoretical techniques, it is found that the simplest HTM, TB-CuPc, is the best-performing HTM primarily due to its higher hole mobility and a more appropriate highest-occupied molecular orbital, whose enables efficient hole extraction without open-circuit voltage (Voc)losses. This derivative leads to PCEs of 19.96%, which are among the highest values for Pc-based HTMs. Importantly, devices incorporating these HTMs present significantly higher stability compared to those based on spiro-OMeTAD. The results here presented pave the way for more realistic, efficient, and inexpensive photovoltaic devices using phthalocyanine derivatives. Herein, Cu(II)Pcs and Ni(II)Pcs peripherally tetra-functionalized with 5-hexylthiophene (HT), 5-hexyl-2,2'-bithiophene (HBT), and tertbutyl groups (TB) are readily synthesized and employed as hole-transporting materials in mixed-ion perovskite ([FAPbI3]0.85[MAPbBr3]0.15) solar cells, achieving power conversion efficiencies up to 20.0%.image (c) 2024 WILEY-VCH GmbH
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    Solar light-driven hydrogen evolution by co-catalyst-free subphthalocyanine-sensitized photocatalysts
    (Royal Soc Chemistry, 2024) Dogan, Sifa; Guntay, Buket; Demircioglu, Perihan Kubra; Akyildiz, Yigit Osman; Aydin, Hasan; Aslan, Emre; Can, Mustafa
    Subphthalocyanines (SubPcs) have emerged as promising organic dyes for the development of efficient artificial photosynthetic devices, offering intense absorption in the visible region along with excellent charge transport properties. In this study, four novel SubPc derivatives containing carboxylic acid and various peripheral substituents were synthesized as a panchromatic photosensitizer to prepare an efficient and stable TiO2-based photocatalytic system for co-catalyst-free photocatalytic hydrogen evolution. To compare the influence of the nature of the peripheral substituents on photocatalytic activity, SubPc derivatives (coded as SubPc 1-4) were decorated with substituents having different electron-donating capabilities, such as alkyl thio, benzodioxin, amine, and iodo units, respectively. Photocatalytic activities were examined in the presence of TEOA as a sacrificial agent under irradiation with lambda > 400 nm without co-catalyst loading. SubPc 1/TiO2 shows the best photocatalytic activity among the SubPc-sensitized photocatalysts, with a hydrogen evolution rate of 0.176 mmol h(-1). While the activity of all four SubPc-based photocatalysts increased significantly after 24 h irradiation, notably, SubPc 1/TiO2 exhibited remarkable catalytic activity, achieving a hydrogen evolution rate of 6.017 mmol with a high turnover number (TON) value of 12 279 for hydrogen production. This study highlights the potential of SubPc-based sensitizers for co-catalyst-free photocatalytic H-2 production and offers valuable insights into the impact of peripheral units in SubPc/TiO2-based photocatalytic systems.
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    Subphthalocyanines for Visible-Light-Driven Hydrogen Evolution: Tuning Photocatalytic Performance with Molecular Design
    (Amer Chemical Soc, 2023) Guntay, Buket; Dogan, Sifa; Killi, Askin; Genc Acar, Eminegul; Demircioglu, Perihan Kubra; Aslan, Emre; Kurtay, Gulbin
    In this work, a series of subphthalocyanines (SubPcs)with a carboxylicacid anchoring group at the axial position were used as photosensitizersof TiO2 for photocatalytic hydrogen evolution from waterunder visible light irradiation. SubPc derivatives with various peripheralsubstituents were successfully prepared to systematically investigatethe dependence of photocatalytic performance on electron-donatingunits (i.e., bisthiophene or thioether) at the peripheral positionof the SubPcs. SubPc 2/TiO2/Pt shows the best photocatalyticactivity among the three dye-sensitized photocatalysts, with a hydrogenevolution rate of 1.104 mmol center dot g(-1)center dot h(-1). After 24 h irradiation, SubPc 2/TiO2/Ptachieved a remarkable catalytic activity for the production of H-2 (19.96 mmol center dot g(-1)) with a TON valueof 40 734 and a high STH efficiency of 2.1%. Density functionaltheory (DFT) and time-dependent DFT (TD-DFT) approaches were usedto elucidate further structural and electrical properties, includingthe interaction patterns of tailored SubPcs. It is worth noting thatthe theoretical computations exhibit good conformity with the empiricaldata. The predicted fluctuations in photocatalytic activity detectedin SubPc systems were shown to be closely associated with frontiermolecular orbital (FMO) characteristics, noncovalent interaction (NCI)patterns, and the electron-donating nature of the fragments locatedat the peripheral positions.
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    Unveiling combat strategies against Candida spp. biofilm structures: Demonstration of photodynamic inactivation with innovative phthalocyanine derivatives
    (Elsevier Science Sa, 2024) Ozturk, Ismail; Ozel, Derya; Dogan, Sifa; Tuncel, Ayca; Yurt, Fatma; Tekintas, Yamac; Demircioglu, Perihan Kubra
    Antimicrobial resistance is an important problem for infection control and therapy. Microorganisms in biofilm structure are remarkably less susceptible to antimicrobials compared to planktonic cells. Increasing rates of resistance to antimicrobials have led to the development of new antimicrobial strategies. Antimicrobial photodynamic therapy (PDT) is an alternative treatment method that may contribute to the fields of infection control and treatment. This study aimed to investigate the antifungal activities of photosensitizers and the anti -biofilm activities of phthalocyanine derivatives on C. albicans and C. parapsilosis strains. The anti -biofilm effects of aPDT on the biofilm of Candida albicans were also visualized via SEM (Scanning Electron Microscopy). Our findings showed that aPDT with phthalocyanines inhibited biofilm production levels and reduced the mature biofilm levels of Candida strains. Additionally, SEM results supported that aPDT application successfully eradicated fungal cells and inhibited the biofilm produced by C. albicans . Although more detailed experiments are needed, we suggest that the use of Pcs in aPDT may be beneficial for the treatment of biofilm-related Candida infections.