کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5439229 1398192 2017 24 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Optical and structural properties of well-aligned ZnO nanoneedle arrays grown on porous silicon substrates by electric field-assisted aqueous solution method
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Optical and structural properties of well-aligned ZnO nanoneedle arrays grown on porous silicon substrates by electric field-assisted aqueous solution method
چکیده انگلیسی
Vertically well-aligned ZnO nanoneedle arrays were successfully grown on porous silicon substrates by electric field-assisted aqueous solution method. Room-temperature photoluminescence (PL), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) analyses were performed to investigate the optical, structural, and morphological properties of the arrays. FESEM results indicated that increasing the current density at the initial stage aided in transforming the ZnO structure from hexagonal to needle-shaped nanorods and in subsequently increasing nanoneedle length. XRD findings showed that ZnO nanoneedles had preferential growth at the (002) orientation, indicating a high degree of ZnO nanoneedle vertical orientation to the substrate surface. Moreover, increased current density resulted in a redshift in the PL peak of ZnO nanorods toward a longer wavelength because of Zn vacancies in the energy band gap of ZnO. In addition, no E1 (LO) mode peak was observed in the Raman spectra of all samples. This finding indicated that nanorod growth was considerably or almost totally free from defects, such as O2 vacancies, Zn interstitials, or their complexes and free carriers.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ceramics International - Volume 43, Issue 1, Part B, January 2017, Pages 1488-1494
نویسندگان
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