کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1529006 | 995729 | 2013 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Solution growth of ZnO microwires and grass architectures
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
مواد الکترونیکی، نوری و مغناطیسی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Solution growth of ZnO microwires and grass architectures Solution growth of ZnO microwires and grass architectures](/preview/png/1529006.png)
چکیده انگلیسی
In spite of extensive research in gold (Au) nanoparticles, it remains a challenge to synthesize structurally homogeneous sample-set with controlled morphologies. The latter critically affect the role of Au nanoparticles as a seed/catalyst for the growth of other nanostructures. Here, we systematically studied and quantified the growth of Au nanoparticles in a single-step chemical synthesis approach and observed the effects of growth temperature and duration, metal salt and surfactant concentration, and surfactant type. These parameters strongly influenced morphological evolution, distribution, and heterogeneities in the as-synthesized Au nanoparticles. Next, the synthesized Au nanoparticles were utilized for the growth of zinc oxide (ZnO) microwires in a solution growth approach. It was observed that Au nanoparticles on the substrate did not catalyze the growth of ZnO microwires but facilitated uniform dispersion of standing microwires. Supported by microscopic analysis, the proposed growth mechanism is heterogeneous nucleation of ZnO on the loosely bound Au nanoparticles on the substrates, favored by lattice match between the ZnO and Au. Based on this mechanism, Au nanoparticles only assisted in the initial stages of ZnO microwire growth. For longer growth duration (~10Â h), over-deposition of ZnO from the solution on already grown wires led to their micron scale diameters as well as grass architectures and making the growth process independent of size and shape of the Au nanoparticles. The formation of ZnO grass architecture is due to attachment of Au nanoparticles on the growing microwire surface, which further served as a heterogeneous nucleation site for the ZnO growth. These Au nanoparticles detached from the Si wafer due to cleavage of AuS bonds or hydrolysis of SiO bonds on the thiolated Si wafer in presence of the ZnO growth precursor (hexamethylenetetramine) and conditions. As-synthesized Au nanoparticles and ZnO microwires were characterized by high-resolution transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Materials Science and Engineering: B - Volume 178, Issue 11, 20 June 2013, Pages 785-793
Journal: Materials Science and Engineering: B - Volume 178, Issue 11, 20 June 2013, Pages 785-793
نویسندگان
Nitin Chopra, Junchi Wu, Wenwu Shi,