Yazarlar
Yayınlar
- MakaleAçık Erişim2025Scopus SJRQ3Tailoring the optoelectronic properties of ZnO nanowires via TiO2 coating
Sarac, Mehmet Fahri; Mert, Merve; Solakyildirim, Tuba; Teber, Ahmet
The photosensing properties of TiO2/ZnO nanowires (NWs) were investigated by sequential deposition using thermal oxidation and sol–gel. It was found that TiO2/ZnO NWs with 5 mM concentration exhibit a higher aspect ratio compared to the 10 mM and 25 mM TiO2/ZnO NWs. The surface-to-volume ratio directly influences the photoluminescence (PL) intensity and electrical properties of the ZnO NWs. XPS confirmed the presence of TiO2 on the surface, while EDS detected titanium, with its concentration increasing as the TiO2 concentration rises. The photosensing performance of ZnO has been significantly improved by modifying it with TiO2. However, determining the optimum concentration is a critical factor in performance improvement. The findings show that high TiO2 concentrations improve surface properties, but excessive coating may limit carrier mobility. Photosensitivity has been increased at lower TiO2 concentration due to a higher surface-to-volume ratio (SVR) and, as a result, higher surface photoactivity. The 25 mM TiO2/ZnO NW array stands out in optimal detectability and photoresponsivity due to the reduced resistance caused by the increased Ti concentration on the surface. The 25 mM TiO2/ZnO NWs achieved the highest photoresponsivity (717 mA/W) and specific detectivity (1.48 × 101° Jones), while the 5 mM TiO2/ZnO NWs exhibited exceptional photosensitivity (320.11%), making them ideal for UV detection. The samples at varying concentrations show promise in photosensitivity, detectability, and photoresponsivity, making them suitable for environmental sensors, UV detectors, and other optoelectronic applications.
AtıfOpenAlex1
İncele - MakaleYalnız künye2017Scopus SJRQ1A study on some physical properties of a Pb-doped GaAs thin film produced by thermionic vacuum arc
Şenay, Volkan; Özen, Soner; Pat, Suat; Korkmaz, Şadan
A 155 nm Pb-doped GaAs thin film was deposited on a glass substrate by means of the thermionic vacuum arc technique in 30 s using GaAs and Pb pellets as source materials. Tools and techniques such as an optical reflectometer, UV-VIS-NIR spectrophotometer, FESEM, EDX, AFM and optical tensiometer were employed to investigate the physical properties of the produced film. From the optical investigations, the refractive index at the wavelength of 632.8 nm and optical band gap of the film were found to be 4.03 and 1.13 eV respectively. It was observed that Pb doping increased the value of refractive index and decreased the band gap value. A uniform surface morphology with fine grain covering the entire surface was observed through the FESEM and AFM studies while 50–80 nm grain size and 2.22 nm root mean square roughness values were obtained. The EDX analysis confirmed the presence of Ga, As and Pb elements in the film. The wetting experiments revealed that the contact angle value was dependent on the liquid used. The surface free energy calculated with OWRK/Fowkes and Equation of State approaches were about 26 mN/m.
AtıfScopus6WoS6OpenAlex5İncele