Photonics / Fotonik

Permanent URI for this collectionhttps://hdl.handle.net/11147/2590

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Now showing 1 - 8 of 8
  • Article
    Citation - WoS: 4
    Citation - Scopus: 3
    Hg(ii)-Mediated Intramolecular Cyclization of Alkynyl Hydrazones: Towards a New Reaction-Based Sensing Approach for Hg(ii) Ions
    (Wiley, 2022) Tütüncü, Büşra Buse; Cebeci, Miray; Emrullahoğlu, Mustafa
    Drawing upon an intramolecular cyclization/annulation reaction sequence mediated by Hg2+ ions, a BODIPY-based fluorescent probe decorated with an alkynyl hydrazone motif responds rapidly and selectively to Hg2+ ions, with a detection limit of 29 nM and a fluorescence turn-on ratio of 15-fold. With the addition of Hg2+ ions, the BODIPY-based alkynyl hydrazone transforms into a pyrazole ring to mediate a turn-on emission response clearly observable to the naked eye under visible light excitation.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    A Cyclopalladated Bodipy Construct as a Fluorescent Probe for Carbon Monoxide
    (Wiley, 2022) Çevik Eren, Merve; Eren, Ahmet; Dartar, Suay; Tütüncü, Büşra Buse; Emrullahoğlu, Mustafa
    By introducing a palladium ion into the backbone of BODIPY, we devised a cyclopalladated BODIPY construct that was almost non-emissive in the absence of any analyte but became highly fluorescent upon interacting with carbon monoxide (CO) in solution and in living cells. A process of ortho-carbonylation and depalladation mediated by the specific binding of CO to palladium, promoted the release of the heavy atom from the fluorophore and consequently generated a fluorescence signal with an exceptionally high (60-fold) enhancement ratio.
  • Article
    Citation - WoS: 29
    Citation - Scopus: 28
    Fabrication, Illumination Dependent Electrical and Photovoltaic Properties of Au/Bod-pyr Schottky Diode
    (Springer, 2021) Ongun, Onur; Taşcı, Enis; Emrullahoğlu, Mustafa; Akın, Ummuhan; Tuğluoğlu, Nihat; Eymur, Serkan
    4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)-based BOD-Pyr compound was synthesized according to the literature and HOMO and LUMO energies of the BOD-Pyr were calculated by DFT/B3LYP/6-311G(d,p) method using on Gaussian 09 W. Au/BOD-Pyr/n-Si/In Schottky diode were fabricated using thermal evaporation and spin coating technique. The electronic and photovoltaic properties of Au/BOD-Pyr/n-Si/In diode have been investigated by current-voltage (I-V) measurements at dark and under various illumination intensities. The calculated ideality factor and barrier height of the diode in dark were found to be 2.84 and 0.75 eV, respectively. These parameters were also obtained under 100 mW/cm(2) illumination level as 1.55 and 0.87 eV, respectively. The values of open-circuit voltage and short circuit current density were obtained as 0.26 V and 0.56 mA/cm(2) under the illumination level of 100 mW/cm(2). These all findings suggest that Au/BOD-Pyr/n-Si/In diode can be used as photodiode in optoelectronic applications.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    A New Fluorescent 'turn On' Probe for Rapid Detection of Biothiols
    (Taylor and Francis Ltd., 2020) Üçüncü, Muhammed; Zeybek, Hüseyin; Karakuş, Erman; Üçüncü, Canan; Emrullahoğlu, Mustafa
    We designed and synthesised a novel molecular probe exhibiting high selectivity and sensitivity towards reactive sulphur species (RSS) over other amino acids and biologically relevant species, as well as scrutinised its spectroscopic behaviours under physiological conditions and in living milieu. We used an electrophilic cyanate group as a masking agent to block the excited state intramolecular proton transfer process of 2-(2-cyanato-3-methoxyphenyl)benzo[d]thiazole (HMBT-OCN), which readily hydrolyses to the highly fluorescent structure, 2-(2'-Hydroxy-3'-methoxyphenyl) benzothiazole (HMBT-OH), in the presence of reactive sulphur species. [GRAPHICS] .
  • Article
    Citation - WoS: 23
    Citation - Scopus: 23
    Bodipy-Vinyl Dibromides as Triplet Sensitisers for Photodynamic Therapy and Triplet-Triplet Annihilation Upconversion
    (Royal Society of Chemistry, 2021) Dartar, Suay; Üçüncü, Muhammed; Karakuş, Erman; Hou, Yuqi; Zhao, Jianzhang; Emrullahoğlu, Mustafa
    We devised a new generation of halogen-based triplet sensitisers comprising geminal dibromides at the vinyl backbone of a BODIPY fluorophore. Incorporating geminal dibromides into the pi-conjugation of BODIPY enhanced intersystem crossing due to the heavy atom effect, which in turn improved the extent of excited triplet states.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 14
    Analysis of Illumination Dependent Electrical Characteristics of Α- Styryl Substituted Bodipy Dye-Based Hybrid Heterojunction
    (Springer, 2021) Kaplan, Nazmiye; Taşcı, Enis; Emrullahoğlu, Mustafa; Gökçe, Halil; Tuğluoğlu, Nihat; Eymur, Serkan
    The alpha-styryl substituted BODIPY compound (BDP-Sty) was synthesized and characterized. The optimize ground state structure, HOMO and LUMO simulations, MEP surface map, and various molecular descriptors of the isolated BDP-Sty compound were investigated by Density Functional Theory at the B3LYP/6-311G (d,p) level. The reverse and forward bias current-voltage (I-V) characteristics of the Au/BDP-Sty/n-Si/In diode showed Schottky diode-like characteristics. An ideality factor (n) and barrier height (phi(b)) values of prepared diode for dark were found as 2.32 and 0.828, respectively. The series resistance (R-s) values were attained from the dV/dln(I) plot and Cheung's H(I) function and their values found for dark as 4.95 k omega and 4.59 k omega, respectively. The lnI - lnV and ln(I-R) - V-R(1/2) characteristics of the Au/BDP-Sty/n-Si/In diode reveal that the conduction mechanism is ohmic at low voltage and that of trap-filled space charge limited current and space charge limited current at higher voltage. The characteristic photodiode parameters of the prepared diode such as open circuit voltage (V-oc), short circuit current density (J(sc)), and photosensitivity (S) have also been investigated. All these results indicate the applicability for Au/BDP-Sty/n-Si/In diode in the field optoelectronic device applications.
  • Article
    Citation - WoS: 16
    Citation - Scopus: 16
    Investigation of Electrical and Photovoltaic Properties of Au/N-si Schottky Diode With Bod-Z Interlayer
    (Springer, 2021) Tezcan, Ali Osman; Eymur, Serkan; Taşcı, Enis; Emrullahoğlu, Mustafa; Tuğluoğlu, Nihat
    4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) based BOD-Z-EN compound was used as an interfacial organic layer to fabrication of Au/BOD-Z-EN/n-Si/In diode. The electrical parameters of Au/BOD-Z-EN/n-Si/In diode such as ideality factor (n), barrier height (phi(b)) and series resistance (R-s) have been investigated through current-voltage (I-V) studies at dark and under various illumination intensities to understand the effect of interlayer on the device properties. The values found for the n varied from 2.33 to 1.55 and the phi(b) ranged from 0.86 to 0.90 eV as the illumination condition changed from dark to 100 mW/cm(2). Series resistance (R-s) values calculated using Cheung's method were found to decrease with increasing illumination level. The forward bias I-V characteristics of the diode were explained by the space charge limited current theory. The main photovoltaic parameters such as open circuit voltage (V-oc), short circuit current density (J(sc)) and fill factor (FF) were determined for various light intensity. The Au/BOD-Z-EN/n-Si/In diode exhibits a photovoltaic behavior with a V-oc of 150 mV and J(sc) of 10 mu A/cm(2) under 100 mw/cm(2). In addition, photosensitivity and photoresponsivity properties of the diode were determined. All these results indicate that Au/BOD-Z-EN/n-Si/In device can be used as photosensor in optoelectronic applications.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 13
    Electrical, Photodiode, and Dft Studies of Newly Synthesized Pi-Conjugated Bodipy Dye-Based Au/Bod-dim Device
    (Elsevier, 2021) Şahin, Muhammet Ferit; Taşcı, Enis; Emrullahoğlu, Mustafa; Gökçe, Halil; Tuğluoğlu, Nihat; Eymur, Serkan
    A pi-conjugated 4,4-difluoro-4- bora-3a,4a-diaza-s-indacene (BODIPY) dimer (BOD-Dim) compound has been synthesized and characterized. The optimized molecular structure, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) simulations, and static isotropic polarizability of the isolated compound were computed via the Gaussian program. The simulated static dielectric constant value was calculated. The effect of the BOD-Dim interlayer on the diode characteristics of the Au/n-Si diode was investigated. The electrical and photovoltaic parameters of the Au/BOD-Dim/n-Si/In diode such as ideality factor (n), barrier height (phi B), open-circuit voltage (Voc), short-circuit current (Jsc), photosensitivity (S), and photoresponsivity (R) have been investigated by current-voltage measurements at dark and under various illumination intensities. The possible current conduction mechanism has been examined through the forward bias ln (IF)-ln(VF) and ln(IR)-VR1/2 characteristics. All obtained results confirmed that Au/BOD-Dim/n-Si/In diode exhibits a photovoltaic behavior and presents great potential as a photosensor for optoelectronic device applications.