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Journal of the American Chemical Society
Nanosheets were electrically characterized by fabricatꢀ
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ing devices using either direct transfer on preꢀfabricated leads,
shadow mask lithography or electronꢀbeam lithography. Using the
first procedure results in bottom contacts (Figure 4a) and yields
top contacts (Figure 4a) with the other two procedures. In all three
cases, devices were similarly resistive, in the Gꢁ range, and
Notes
The authors declare no competing financial interests.
ACKNOWLEDGMENT
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This work was supported by the National Science Foundation
MRSEC program at the University of Utah under grant #DMR
1121252. We gratefully acknowledge Brian van Devener and
Paulo Perez for help with TEM data. We also gratefully
acknowledge Jonathan David Ogle for assistance with Raman
data and Emily Fullwood for help with acquiring TGA data.
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Figure 4: Electrical characterization of 1-Ni. (a) (top) Top contact and
(bottom) bottom contact scheme of electrical contacts. (b) Typical topꢀ
contact device architecture using eꢀbeam lithography. (c) Temperature
dependent conductance of 2-Ni. (d) Back gate Vbg dependent conductꢀ
a)
b)
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ance of 1-Ni (20 nm).
REFERENCES
(1)
Geim, A. K.; Novoselov, K. S. Nat. Mater. 2007, 6,
183.
(2)
Lin, Y. M.; Dimitrakopoulos, C.; Jenkins, K. A.;
Farmer, D. B.; Chiu, H. Y.; Grill, A.; Avouris, P. Science 2010,
327, 662.
(3)
Novoselov, K. S.; Geim, A. K.; Morozov, S. V.; Jiang,
0.98
D.; Zhang, Y.; Dubonos, S. V.; Grigorieva, I. V.; Firsov, A. A.
Science 2004, 306, 666.
c)
(4)
151.
(5)
444, 347.
(6)
Maassen, J.; Ji, W.; Guo, H. Nano Letters 2011, 11,
Son, Y.ꢀW.; Cohen, M. L.; Louie, S. G. Nature 2006,
Miao, X.; Tongay, S.; Petterson, M. K.; Berke, K.;
0.49
0.00
Rinzler, A. G.; Appleton, B. R.; Hebard, A. F. Nano Lett. 2012,
12, 2745.
Temperature (K)
showed slight modulation of conductance G with respect to variaꢀ
tion of a back gate voltage Vbg. Figure 4d shows a typical gateꢀ
dependent conductance of a Ni nanosheet device. Finally, Figure
4c shows the temperature dependent conductance of a different Ni
nanosheet device down to 4K from room temperature. In general,
devices tended to decrease in conductance as temperature was
lowered indicating insulating behavior in charge transport.
(7)
(8)
Wang, X.; Zhi, L.; Müllen, K. Nano Lett. 2008, 8, 323.
Liu, Y.; Artyukhov, V. I.; Liu, M.; Harutyunyan, A. R.;
Yakobson, B. I. J. Phys. Chem. Lett. 2013, 4, 1737.
(9) Campbell, M. G.; Sheberla, D.; Liu, S. F.; Swager, T.
M.; Dinca, M. Angew. Chem., Int. Ed. 2015, 54, 4349.
(10) Clough, A. J.; Yoo, J. W.; Mecklenburg, M. H.;
Marinescu, S. C. J. Am. Chem. Soc. 2015, 137, 118.
(11) Huang, X.; Sheng, P.; Tu, Z.; Zhang, F.; Wang, J.;
In conclusion, we synthesized a family of hexaaminoꢀ
benzene based Coordination Polymers (CPs) having a hexagonal
honeycomb crystal lattice. The morphology, composition, and
crystal structure of the complexes were confirmed by OM, FEꢀ
SEM, AFM, XPS and S/TEM. Both top and bottom contacts used
for electrical characterizations yielded similar values of resistancꢀ
es. We attribute the low conductivity of the samples to the low
crystallinity of the framework resulting in crystal defects and
grain boundaries. Efforts towards the synthesis of samples with
lower defects by optimizing reaction conditions and fabrication
techniques are currently underway.
Geng, H.; Zou, Y.; Di, C.ꢀa.; Yi, Y.; Sun, Y.; Xu, W.; Zhu, D.
Nat. Commun. 2015, 6.
(12)
Kambe, T.; Sakamoto, R.; Hoshiko, K.; Takada, K.;
Miyachi, M.; Ryu, J.ꢀH.; Sasaki, S.; Kim, J.; Nakazato, K.;
Takata, M.; Nishihara, H. J. Am. Chem. Soc. 2013, 135, 2462.
(13)
Pal, T.; Kambe, T.; Kusamoto, T.; Foo, M. L.;
Matsuoka, R.; Sakamoto, R.; Nishihara, H. ChemPlusChem 2015,
80, 1255.
(14)
Sakamoto, R.; Hoshiko, K.; Liu, Q.; Yagi, T.;
Nagayama, T.; Kusaka, S.; Tsuchiya, M.; Kitagawa, Y.; Wong,
W.ꢀY.; Nishihara, H. Nat. Commun. 2015, 6.
(15)
Sheberla, D.; Sun, L.; BloodꢀForsythe, M. A.; Er, S.;
ASSOCIATED CONTENT
Supporting Information
Wade, C. R.; Brozek, C. K.; AspuruꢀGuzik, A.; Dinca, M. J. Am.
Chem. Soc. 2014, 136, 8859.
(16)
Dong, R.; Pfeffermann, M.; Liang, H.; Zheng, Z.; Zhu,
Experimental Details, FEꢀSEM, HRꢀTEM, SAED, XPS, S/TEMꢀ
EDS data and electrical characterization data. This material is
X.; Zhang, J.; Feng, X. Angew. Chem., Int. Ed. 2015, 54, 12058.
17)
Dong, R.; Pfeffermann, M.; Liang, H.; Zheng, Z.; Zhu,
X.; Zhang, J.; Feng, X. Angew. Chem., Int. Ed. 2015, 54, 12058.
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