Supporting information Enhanced photoresponse of SnSe ...
Supporting information
Enhanced photoresponse of SnSe nanocrystals decorated WS2 monolayer phototransistor Zhiyan Jia, Jianyong Xiang,* Fusheng Wen, Ruilong Yang, Chunxue Hao, Zhongyuan Liu* State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, 066004, People’s Republic of China,
*Corresponding authors. Email: [email protected] (J. Y. Xiang), [email protected] (Z. Y. Liu)
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Fig. S1. (a) Schematic illustration of synthesis of SnSe nanocrystals (NCs), growth of WS2 monolayers, and fabrication of WS2 monolayer-based phototransistors. (b) Temperature profiles for heaters 1 and 2 during the growth of WS2 monolayers.
Fig. S2. AFM image of a WS2 monolayer. Inset shows the height profile.
Fig. S3. Ids vs Vds curves at the gate voltages of 0 and 20 V for the only WS2 monolayer and WS2/SnSe hybrid phototransistors. S-2
Fig. S4. Typical Raman spectra for the only WS2 monolayer device, WS2/SnSe device, and as prepared SnSe powder. For the hybrid device, beside those peaks of monolayer WS2, two extra peaks were evident at 127.8 cm-1 and 148.4 cm-1, which corresponding to the Ag2 and Ag3 Raman mode of SnSe, respectively.
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Figure S5 A schematic energy level diagram for the hybrid device. After the SnSe NCs were dropped on the monolayer WS2, electrons can flow from WS2 into the SnSe NCs (due to the lower electron affinity energy of SnSe) till the Fermi energies are in the same level, resulting in the formation of a built-in field at the p-n junction. Under illumination of visible light, the photoexcited electrons and holes are separated at the interface of SnSe/WS2. When illuminating with lights in the near infrared region, the photogenerated charges were injected from SnSe NCs into WS2, resulting in the extended photoresponse spectra.
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Table S1 Photoresponse performance at room temperature for only WS2 device, WS2/SnSe hybrid device, WS2 and metal dichalcogenides reported by other research group. L/W refers to the length and width of the conducting channel. Material
Device architecture
L/W (μm)
Responsivity （mA/W）
light
Response time (ms)
Room temperature mobility
Ref.
2 -1 -1
(cm V s )
Monolayer WS2(CVD)
3 terminal FET
6.6/8.8
Visible
6.6
4.1 (rise) 5.2 (decay)
0.1(dark)
This work
Monolayer WS2(CVD)/SnSe
3 terminal FET
6.6/8.8
Visible and infrared
99
8.2 (rise) 8.4 (decay)
2.2(dark)
This work
Multilayer WS2(CVD)
2 terminal
50/500
Visible
≈9.2×10
5.3
N/A
1
Monolayer WS2(CVD)
3 terminal FET
30/230
532 nm
18.8 (Vg=60V)
＜4.5
0.91(dark)
2
Multilayer WS2(exfoliated)
3 terminal FET
15/20
Red(633nm ) and White (LED)
5.7×10
＜20
12(dark)
3
SnSe nanoplates(CVD)
3 terminal FET
1/5.2
Visible
3.3×10
N/A
1.5(dark)
4
SnSe nanosheets films(hydrotherm al method)
3 terminal FET (interdigital electrode)
10/200
Visible
≈26.4
190
N/A
5
SnSe nanocrystals(hydr othermal method)
2 terminal (Interdigital electrode)
10/300 0
Solar simulator
≈4.47×10
N/A
N/A
6
2 terminal
2.4/3.1
530 nm
1.1×10
14.5 (rise) 8.1 (decay)
N/A
7
3 terminal FET
2.6/2.1
473 nm
1×10
22s(rise) 11 (decay)
N/A
8
Few layer SnS2(CVD)
3 terminal FET
5/19.6
450 nm
≈2×10
42 (rise) 42 (decay)
N/A
9
Multilayer SnS2(CVD)
3 terminal FET
2/10
457 nm
8.8
5x10-3 (rise) 7x10-3 (decay)
N/A
10
nanocrystals
Few layer SnSe2 flakes(CVD) Multilayer layer SnS2 nanosheets(CVD)
-2
3
5
-5
S-5
6
5
3
References 1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Lόpez, N. P.; Elías, A. L.; Berkdemir, A.; Beltran, A. C.; C. B.; Gutiérrez, H. R.; Feng, S. M.; Lv, R. T.; Hayashi, T.; H.; Urías, F. L.; Ghosh, S.; Muchharla, B.; Talapatra, S.; Terrones, H. Terrones, M. Photosensor Device Based on Few-layered WS2 Films. Adv. Funct. Mater. 2013, 23, 5511-5517. Lan, C. Y.; Li, C.; Yin, Yi.; Liu, Y.; Large-area synthesis of monolayer WS2 and its ambient-sensitive photo-detecting performance. Nanoscale, 2015, 7, 5974. Huo, N. J.; Yang, S. X.; Wei, Z. M.; Li, S. S.; Xia, J. B.; Li, J. B. Photoresponsive and Gas Sensing Field-Effect Transistors based on Multilayer WS2 Nanoflakes. Scientific Reports. 2015, 4, 5209. Zhao, S. L.; Wang, H.;Zhou, Y.; Liao, L.; Jiang, Y.; Yang, X.; Chen, G. C.; Lin, M.; Wang, Y.; Peng, H. L.; Liu, Z. F.; Controlled synthesis of singlecrystal SnSe nanoplates. Nano Research. 2015, 8, 288-295. Li, L.; Chen, Z.; Hu, Y.; Wang, X. W.; Zhang, T.; Chen, W.; Wang, Q. B. Single-layer Single-Crystalline SnSe Nanosheets. J. Am. Chem. Soc. 2013, 135, 1213-1216. Baumgardner, W. J.; Choi, J. J.; Lim, Y. F.; Hanrath, T. SnSe Nanocrystals: Synthesis, Structure, Optical Properties, and Surface Chemistry. J. Am. Chem. Soc. 2010, 132, 9519-9521. Zhou, X.; Gan, L.; Tian, W. M.; Zhang, Q.; Jin, S. Y.; Li, H. Q.; Bando, Y.; Golberg, D.; Zhai, T. Y. Ultrathin SnSe2 Flakes Grown by Chemical Vapor Deposition for High-performance Photodetectors. Adv. Mater. 2015, 27, 80358041. Huang, Y.; Deng, H. X.; Xu, K.; Wang, Z. X.; Wang, Q. S.; Wang, F. M.; Wang, F.; Zhan, X. Y.; Li, S. S.; Luo, J. W.; He, J. Highly sensitive and fast phototransistor based on large size CVD-grown SnS2 nanosheets. Nanoscale, 2015, 7, 14093. Xia, J.; Zhu, D. D.; Wang, L.; Huang, B.; Huang, X.; Meng, X. M. LargeScale Growth of Two-Dimensional SnS2 Crystals Driven by Screw Dislocations and Application to Photodetectors. Adv. Funct. Mater. 2015, 25, 4255-4261. Su, G. X.; Hadjiev, V. G.; Loya, P. E.; Zhang, J.; Lei, S. D.; Maharjan, S.; Dong, P.; Ajayan, P. M.; Lou, J.; Peng, H. B. Chemical Vapor Deposition of Thin Crystals of Layered Semiconductor SnS2 for Fast Photodetection Application. Nano lett. 2015, 15, 506-513.
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Enhanced photoresponse of SnSe nanocrystals decorated WS2 monolayer phototransistor Zhiyan Jia, Jianyong Xiang,* Fusheng Wen, Ruilong Yang, Chunxue Hao, Zhongyuan Liu* State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, 066004, People’s Republic of China,
*Corresponding authors. Email: [email protected] (J. Y. Xiang), [email protected] (Z. Y. Liu)
S-1
Fig. S1. (a) Schematic illustration of synthesis of SnSe nanocrystals (NCs), growth of WS2 monolayers, and fabrication of WS2 monolayer-based phototransistors. (b) Temperature profiles for heaters 1 and 2 during the growth of WS2 monolayers.
Fig. S2. AFM image of a WS2 monolayer. Inset shows the height profile.
Fig. S3. Ids vs Vds curves at the gate voltages of 0 and 20 V for the only WS2 monolayer and WS2/SnSe hybrid phototransistors. S-2
Fig. S4. Typical Raman spectra for the only WS2 monolayer device, WS2/SnSe device, and as prepared SnSe powder. For the hybrid device, beside those peaks of monolayer WS2, two extra peaks were evident at 127.8 cm-1 and 148.4 cm-1, which corresponding to the Ag2 and Ag3 Raman mode of SnSe, respectively.
S-3
Figure S5 A schematic energy level diagram for the hybrid device. After the SnSe NCs were dropped on the monolayer WS2, electrons can flow from WS2 into the SnSe NCs (due to the lower electron affinity energy of SnSe) till the Fermi energies are in the same level, resulting in the formation of a built-in field at the p-n junction. Under illumination of visible light, the photoexcited electrons and holes are separated at the interface of SnSe/WS2. When illuminating with lights in the near infrared region, the photogenerated charges were injected from SnSe NCs into WS2, resulting in the extended photoresponse spectra.
S-4
Table S1 Photoresponse performance at room temperature for only WS2 device, WS2/SnSe hybrid device, WS2 and metal dichalcogenides reported by other research group. L/W refers to the length and width of the conducting channel. Material
Device architecture
L/W (μm)
Responsivity （mA/W）
light
Response time (ms)
Room temperature mobility
Ref.
2 -1 -1
(cm V s )
Monolayer WS2(CVD)
3 terminal FET
6.6/8.8
Visible
6.6
4.1 (rise) 5.2 (decay)
0.1(dark)
This work
Monolayer WS2(CVD)/SnSe
3 terminal FET
6.6/8.8
Visible and infrared
99
8.2 (rise) 8.4 (decay)
2.2(dark)
This work
Multilayer WS2(CVD)
2 terminal
50/500
Visible
≈9.2×10
5.3
N/A
1
Monolayer WS2(CVD)
3 terminal FET
30/230
532 nm
18.8 (Vg=60V)
＜4.5
0.91(dark)
2
Multilayer WS2(exfoliated)
3 terminal FET
15/20
Red(633nm ) and White (LED)
5.7×10
＜20
12(dark)
3
SnSe nanoplates(CVD)
3 terminal FET
1/5.2
Visible
3.3×10
N/A
1.5(dark)
4
SnSe nanosheets films(hydrotherm al method)
3 terminal FET (interdigital electrode)
10/200
Visible
≈26.4
190
N/A
5
SnSe nanocrystals(hydr othermal method)
2 terminal (Interdigital electrode)
10/300 0
Solar simulator
≈4.47×10
N/A
N/A
6
2 terminal
2.4/3.1
530 nm
1.1×10
14.5 (rise) 8.1 (decay)
N/A
7
3 terminal FET
2.6/2.1
473 nm
1×10
22s(rise) 11 (decay)
N/A
8
Few layer SnS2(CVD)
3 terminal FET
5/19.6
450 nm
≈2×10
42 (rise) 42 (decay)
N/A
9
Multilayer SnS2(CVD)
3 terminal FET
2/10
457 nm
8.8
5x10-3 (rise) 7x10-3 (decay)
N/A
10
nanocrystals
Few layer SnSe2 flakes(CVD) Multilayer layer SnS2 nanosheets(CVD)
-2
3
5
-5
S-5
6
5
3
References 1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Lόpez, N. P.; Elías, A. L.; Berkdemir, A.; Beltran, A. C.; C. B.; Gutiérrez, H. R.; Feng, S. M.; Lv, R. T.; Hayashi, T.; H.; Urías, F. L.; Ghosh, S.; Muchharla, B.; Talapatra, S.; Terrones, H. Terrones, M. Photosensor Device Based on Few-layered WS2 Films. Adv. Funct. Mater. 2013, 23, 5511-5517. Lan, C. Y.; Li, C.; Yin, Yi.; Liu, Y.; Large-area synthesis of monolayer WS2 and its ambient-sensitive photo-detecting performance. Nanoscale, 2015, 7, 5974. Huo, N. J.; Yang, S. X.; Wei, Z. M.; Li, S. S.; Xia, J. B.; Li, J. B. Photoresponsive and Gas Sensing Field-Effect Transistors based on Multilayer WS2 Nanoflakes. Scientific Reports. 2015, 4, 5209. Zhao, S. L.; Wang, H.;Zhou, Y.; Liao, L.; Jiang, Y.; Yang, X.; Chen, G. C.; Lin, M.; Wang, Y.; Peng, H. L.; Liu, Z. F.; Controlled synthesis of singlecrystal SnSe nanoplates. Nano Research. 2015, 8, 288-295. Li, L.; Chen, Z.; Hu, Y.; Wang, X. W.; Zhang, T.; Chen, W.; Wang, Q. B. Single-layer Single-Crystalline SnSe Nanosheets. J. Am. Chem. Soc. 2013, 135, 1213-1216. Baumgardner, W. J.; Choi, J. J.; Lim, Y. F.; Hanrath, T. SnSe Nanocrystals: Synthesis, Structure, Optical Properties, and Surface Chemistry. J. Am. Chem. Soc. 2010, 132, 9519-9521. Zhou, X.; Gan, L.; Tian, W. M.; Zhang, Q.; Jin, S. Y.; Li, H. Q.; Bando, Y.; Golberg, D.; Zhai, T. Y. Ultrathin SnSe2 Flakes Grown by Chemical Vapor Deposition for High-performance Photodetectors. Adv. Mater. 2015, 27, 80358041. Huang, Y.; Deng, H. X.; Xu, K.; Wang, Z. X.; Wang, Q. S.; Wang, F. M.; Wang, F.; Zhan, X. Y.; Li, S. S.; Luo, J. W.; He, J. Highly sensitive and fast phototransistor based on large size CVD-grown SnS2 nanosheets. Nanoscale, 2015, 7, 14093. Xia, J.; Zhu, D. D.; Wang, L.; Huang, B.; Huang, X.; Meng, X. M. LargeScale Growth of Two-Dimensional SnS2 Crystals Driven by Screw Dislocations and Application to Photodetectors. Adv. Funct. Mater. 2015, 25, 4255-4261. Su, G. X.; Hadjiev, V. G.; Loya, P. E.; Zhang, J.; Lei, S. D.; Maharjan, S.; Dong, P.; Ajayan, P. M.; Lou, J.; Peng, H. B. Chemical Vapor Deposition of Thin Crystals of Layered Semiconductor SnS2 for Fast Photodetection Application. Nano lett. 2015, 15, 506-513.
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