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Temperature effects on the growth of SnS nanosheet structure using
thermal decomposition
Bo-Jia Huang, Jyun-Jia Huang, Sheng-Chang Wang*
Department of Mechanical Engineering, Southern Taiwan University
Tainan, TAIWAN
*E-mail: [email protected]
指導教授：王聖璋 博士(Pro.S-C Wang)
學生:黃伯嘉(Bo-Jia Huang)
2016/7/15
Results and Discussion
Results and Discussion
X-ray diffraction patterns obtained for SnS powder synthesized at different
deposition potential are shown in Fig .2 a-b. All peaks in Fig.2a-b can be
indexed to these of the orthorhombic SnS.the relative intensity of the peaks
corresponding to the strongest peak(040)planes to that of (111) planes varies
significantly from the reported values.
Fig. 2 XRD patterns of SnS powder at various potentials : (a)at 220°C
(b)at 280°C
Results and Discussion
The morphology of the SnS powder synthesized at 280°C was studied by SEM
and TEM, which are shown in Fig. 3 (a) and (b). The shape of the SnS sample is
flower-like composed by several sheet structures, which is observed by TEM
image. The diffraction pattern of the irregular sheet structure is confirmed as the
single crystal SnS phase, as shown in fig. 3 (c).
Fig 3 Decomposition temperature at 220°C SnS crystal structure image.
(a) SnS SEM (b)SnS TEM (c) SAED pattern
Results and Discussion
As the synthesis temperature increase to 280°C, the SnS morphology is
changed to regular square sheet, as shown in SEM image of Fig. 4(a). The
TEM image is further confirmed that the morphology of SnS is a squared
sheet with rounded-corner. The TEM image shows uniformed contrast with
some bending contour fringes in the nanosheet, which identify the sheet is 1
min edge length with very thin and uniform in thickness.
Compared the TEM image and it corresponding diffraction pattern, we can
conclude the that the edge direction of the nanosheet is <101> and the
sheet plane is (010).
Fig 4 Decomposition temperature at 280°C SnS crystal structure image.
(a)SnS SEM (b)SnS TEM (c) SAED pattern
Results and Discussion
The representative optical absorption spectrum of the two kinds of SnS structures is
shown in Fig. 5. This figure indicated that the both SnS structures have high absorption
in the range of ultraviolet. The nanosheet SnS structure has a higher absorption than
the flower-like SnS.
Fig 5 SnS film on ITO glass absorption spectrum(A) flower
like (B) sheet structure
Conclusion
Conclusion
The two-dimensional SnS crystal were synthesized by hydrothermal decomposition
using Sn(OA)2 and S powder as sources in OLA solovent. The results show that a flowerlike SnS structure composed of several irregular flakes is synthesized at 220°C. A
squared SnS nanosheet with rounded-corner structure is synthesize by 280°C. The
nanosheet SnS structure has a higher absorption than the flower-like SnS
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