Araştırma Çıktıları | WoS | Scopus | TR-Dizin | PubMed

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Browsing Araştırma Çıktıları | WoS | Scopus | TR-Dizin | PubMed by browse.metadata.publisher "Aip Publishing"

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    Citation - WoS: 27
    Effect of Van Der Waals Interactions on the Chemisorption and Physisorption of Phenol and Phenoxy on Metal Surfaces
    (Aip Publishing, 2016) Pekoz, Rengin; Donadio, Davide
    The adsorption of phenol and phenoxy on the (111) surface of Au and Pt has been investigated by density functional theory calculations with the conventional PBE functional and three different non-local van derWaals (vdW) exchange and correlation functionals. It is found that both phenol and phenoxy on Au(111) are physisorbed. In contrast, phenol on Pt(111) presents an adsorption energy profile with a stable chemisorption state and a weakly metastable physisorbed precursor. While the use of vdW functionals is essential to determine the correct binding energy of both chemisorption and physisorption states, the relative stability and existence of an energy barrier between them depend on the semi-local approximations in the functionals. The first dissociation mechanism of phenol, yielding phenoxy and atomic hydrogen, has been also investigated, and the reaction and activation energies of the resulting phenoxy on the flat surfaces of Au and Pt were discussed. Published by AIP Publishing.
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    Citation - WoS: 5
    Citation - Scopus: 5
    Revealing Defect Centers in Pbwo4 Single Crystals Using Thermally Stimulated Current Measurements
    (Aip Publishing, 2024) Isik, M.; Gasanly, N. M.
    The trap centers have a significant impact on the electronic properties of lead tungstate (PbWO4), suggesting their crucial role in optoelectronic applications. In the present study, we investigated and revealed the presence of shallow trap centers in PbWO4 crystals through the utilization of the thermally stimulated current (TSC) method. TSC experiments were performed in the 10-280 K range by applying a constant heating rate. The TSC spectrum showed the presence of a total of four peaks, two of which were overlapped. As a result of analyzing the TSC spectrum using the curve fit method, the activation energies of revealed centers were found as 0.03, 0.11, 0.16, and 0.35 eV. The trapping centers were associated with hole centers according to the comparison of TSC peak intensities recorded by illuminating the opposite polarity contacts. Our findings not only contribute to the fundamental understanding of the charge transport mechanisms in PbWO4 crystals but also hold great promise for enhancing their optoelectronic device performance. The identification and characterization of these shallow trap centers provide valuable insights for optimizing the design and fabrication of future optoelectronic devices based on PbWO4.