کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1489741 | 992311 | 2011 | 6 صفحه PDF | دانلود رایگان |
The present report details the effects of synthesis time, concentrations of hexamethylenetetramine (HMTA) and precursor tin (II) chloride solutions on the self-assembly of SnO2 nanocrystals. High-resolution electron microscopy images revealed that the structures were made of randomly attached SnO2 nanocrystals with sizes in between ∼2 and 5 nm. X-ray photoelectron spectroscopy (XPS) showed that the Sn3d region was characterized by the spin-orbit splitting of the Sn3d5/2 ground state at ∼487.6 eV and by the Sn3d3/2 excited state at ∼496.1 eV, which was attributed to the Sn+4 oxidation state of the SnO2 samples. We also found that the self-assembly could be achieved only with aqueous tin (II) chloride solution, and not with aqueous stannic (IV) chloride solution. A plausible growth mechanism is proposed in order to analyze the distinctive self-assembly of SnO2 nanocrystals in the presence of aqueous HMTA solution.
Figure optionsDownload as PowerPoint slideResearch highlights▶ Synthesis details self-assembly of SnO2 in aqueous hexamethylenetetramine solution. ▶ Hydrogen bonds clustering around the hexamethylenetetramine interact with the non-polar SnO2 surfaces. ▶ Self-assembly was possible with aqueous tin (II) chloride solution and not with aqueous tin (IV) chloride solution.
Journal: Materials Research Bulletin - Volume 46, Issue 4, April 2011, Pages 609–614