Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
Browse
3 results
Search Results
Article Citation - WoS: 15Citation - Scopus: 17Investigation of the Performance and Properties of ZnO/GO Double-Layer Supercapacitor(Pergamon-Elsevier Science Ltd, 2024-08) Buyukkurkcu, Handan; Durmus, Ali; Colak, Hakan; Kurban, Rifat; Sahmetlioglu, Ertugrul; Karakose, ErcanComposite electrode material was formed by mixing reduced graphene oxide (rGO) and zinc oxide (ZnO) compound, using the Hummers and green synthesis methods, respectively. Of rGO powder, 10 g was mixed with 10%, 20% and 30% ZnO, and composite electrodes were obtained by using 10% binder. The energy storage performance and structural characteristics of the supercapacitor were evaluated by analyzing the capacitance values of the synthesized electrodes. The structural characterization of ZnO/rGO composites was performed using X-ray diffraction and field-emission scanning electron microscopy. The electrochemical properties of the ZnO/GO electrodes were analyzed by cyclic voltammetry, electrochemical impedance and galvanostatic charge -discharge tests. The specific capacitance value of electrodes increased as zinc content increased in the ZnO/ rGO composite material used to produce electrodes. The maximum specific capacitance values were measured at 5 mV/s scanning rate as 194.23 (rGO), 366.81 (10% ZnO), 383.18 (20% ZnO) and 410.48 F/g (30% ZnO). In conclusion, the use of composite material formed by the combination of ZnO nanoparticles obtained by green synthesis method from orange peel and graphene oxide increased the electrochemical efficiency of the supercapacitor.Article Citation - WoS: 63Citation - Scopus: 64Effective Neural Photostimulation Using Indium-Based Type-II Quantum Dots(Amer Chemical Soc, 2018-07-18) Jalali, Houman Bahmani; Aria, Mohammad Mohammadi; Dikbas, Ugur Meric; Sadeghi, Sadra; Kumar, Baskaran Ganesh; Sahin, Mehmet; Nizamoglu, Sedat; Ganesh Kumar, Baskaran; Bahmani Jalali, Houman; Mohammadi Aria, MohammadLight-induced stimulation of neurons via photoactive surfaces offers rich opportunities for the development of therapeutic methods and high-resolution retinal prosthetic devices. Quantum dots serve as an attractive building block for such surfaces, as they can be easily functionalized to match the biocompatibility and charge transport requirements of cell stimulation. Although indium based colloidal quantum dots with type-I band alignment have attracted significant attention as a nontoxic alternative to cadmium-based ones, little attention has been paid to their photovoltaic potential as type-II heterostructures. Herein, we demonstrate type-II indium phosphide/zinc oxide core/shell quantum dots that are incorporated into a photoelectrode structure for neural photostimulation. This induces a hyperpolarizing bioelectrical current that triggers the firing of a single neural cell at 4 mu W mm(-2), 26-fold lower than the ocular safety limit for continuous exposure to visible light. These findings show that nanomaterials can induce a biocompatible and effective biological junction and can introduce a route in the use of quantum dots in photoelectrode architectures for artificial retinal prostheses.Article Citation - WoS: 16Citation - Scopus: 18Structurally Colored Physically Unclonable Functions With Ultra-Rich and Stable Encoding Capacity(Wiley-VCH Verlag GmbH, 2025) Esidir, Abidin; Ren, Miaoning; Pekdemir, Sami; Kalay, Mustafa; Kayaci, Nilgun; Gunaltay, Nail; Onses, Mustafa SerdarIdentity security and counterfeiting assume a critical importance in the digitized world. An effective approach to addressing these issues is the use of physically unclonable functions (PUFs). The overarching challenge is a simultaneous combination of extremely high encoding capacity, stable operation, practical fabrication, and a widely available readout mechanism. Herein this challenge is addressed by designing an optical PUF via exploiting the thickness-dependent structural color formation in nanoscopic films of ZnO. The structural coloration ensures authentication using widely available bright-field-based optical readout, whereas the metal oxide provides a high degree of structural stability. True physical randomness in spatial position is achieved by physical vapor deposition of ZnO through stencil masks that are fabricated by pore formation in polycarbonate membranes via photothermal processing of stochastically positioned plasmonic nanoparticles. Structural coloration emerges from thin film interference as confirmed via simulation studies. The rich color variation and stochastic definition of domain size and geometry result in chaotic features with an encoding capacity that approaches (6.4 x 105)(2752x2208). Deep learning-based authentication is further demonstrated by transforming these chaotic features into unbreakable codes without field limitations. This ultra-rich encoding capacity, coupled with outstanding thermal and chemical stability, forms a new cutting edge for state-of-the-art PUF-based encoding systems.