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Indium Tin Oxide Nanowire Networks as Effective UV/Vis Photodetection Platforms.

Zhao S, Choi D, Lee T, Boyd AK, Barbara P, Van Keuren E, Hahm JI - J Phys Chem C Nanomater Interfaces (2014)

Bottom Line: The photoresponsivity of the ITO NW devices ranges from 0.07 to 0.2 A/W at a 3 V bias, whose values are in the performance range of most commercial UV/vis photodetectors.Such useful photodetector characteristics from our ITO NW mesh devices are attained straightforwardly without the need for complicated fabrication procedures involving highly specialized lithographic tools.Therefore, our approach of ITO NW network-based photodetectors can serve as a convenient alternative to commercial or single NW-based devices.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Georgetown University , 37th & O Streets NW, Washington, DC 20057, United States ; College of Science, China University of Petroleum , Beijing 102249, People's Republic of China.

ABSTRACT

We demonstrate that indium tin oxide nanowires (ITO NWs) and cationic polymer-modified ITO NWs configured in a network format can be used as high performing UV/vis photodetectors. The photovoltage response of ITO NWs is much higher than similarly constructed devices made from tin oxide, zinc tin oxide, and zinc oxide nanostructures. The ITO NW mesh-based devices exhibit a substantial photovoltage (31-100 mV under illumination with a 1.14 mW 543 nm laser) and photocurrent (225-325 μA at 3 V). The response time of the devices is fast with a rise time of 20-30 μs and a decay time of 1.5-3.7 ms when probed with a 355 nm pulsed laser. The photoresponsivity of the ITO NW devices ranges from 0.07 to 0.2 A/W at a 3 V bias, whose values are in the performance range of most commercial UV/vis photodetectors. Such useful photodetector characteristics from our ITO NW mesh devices are attained straightforwardly without the need for complicated fabrication procedures involving highly specialized lithographic tools. Therefore, our approach of ITO NW network-based photodetectors can serve as a convenient alternative to commercial or single NW-based devices.

No MeSH data available.


Related in: MedlinePlus

(a) Typicalphotovoltage acquired from ITO NWs while illuminatingthe device with a 543 nm laser through an optical chopper is shown.(b) Photovoltage signal from SnO2, ZTO, and ZnO nanostructuresis recorded when using the same light source as (a). (c) Typical photovoltagesignal obtained from ITO NW devices when using a 355 nm pulsed laseris provided. The inset is a zoomed-in view with the light on to showclearly the rise time.
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fig2: (a) Typicalphotovoltage acquired from ITO NWs while illuminatingthe device with a 543 nm laser through an optical chopper is shown.(b) Photovoltage signal from SnO2, ZTO, and ZnO nanostructuresis recorded when using the same light source as (a). (c) Typical photovoltagesignal obtained from ITO NW devices when using a 355 nm pulsed laseris provided. The inset is a zoomed-in view with the light on to showclearly the rise time.

Mentions: The device schematicprovided in Figure 2(a) displays a typicalsample configuration involving networks ofITO NWs. Figure 2(a) also displays a representativevoltage response obtained from ITO NWs, showing a maximum photovoltage(Vph) value of 31 mV. Down (up) arrowsinserted in Figure 2 indicate the time whenthe 543 nm laser directed to the sample is on (off) through a 400Hz chopper wheel. In comparison, Figure 2(b)displays typical photovoltage plots acquired from the other threetypes of devices consisting of SnO2 NWs, ZnO NRs, and ZTONBs. The voltage responses upon illumination on these materials aresignificantly lower than what we observe from ITO NWs. Both ZnO NRand ZTO NB devices result in Vph of ∼3mV, whereas SnO2 NWs produce an even weaker signal of ∼2mV. Although the exact origin of the increased photovoltage responseobserved from ITO NWs in comparison to other nanomaterials is notclear yet, various inherent electrical properties of the materials,such as charge carrier density, resistivity, and carrier mobility,may contribute to this effect. The corresponding values for an ITOthin film, for example, are, respectively, reported to be on the orderof 5 × 1020/cm3, 2 × 10–4 Ω·cm, and 55 cm2/(V·s),12,13 whereas those of a ZnO thin film are 10 × 1019/cm3, 1 × 10–2 Ω·cm, and 35cm2/(V·s).14 The highercharge carrier density and mobility combined with the lower resistivityof ITO may promote the enhanced photoinduced voltage signal in ourexperiment. The magnitude of Vph varieson the same sample devices depending on the laser position. The laserspot is kept on the sample location, producing the highest signalfor all devices characterized in Figure 2.When comparing the highest Vph of thedifferent devices, the photoresponse of ITO NWs is an order of magnitudelarger than other similar semiconducting oxide nanomaterials shownin Figure 2(b). Therefore, herein we focusour discussion of this paper on ITO NWs. The response time of thephotovoltage change of the ITO NW device is determined by using thepulsed Nd:YAG laser as a light source. Figure 2(c) displays the typical response time of the ITO NW photodetectorswhich is defined collectively by the rise (Tr) and decay (Td) time. The responsetime of ITO NW devices is determined as Tr = 20 μs and Td = 1.5 ms.


Indium Tin Oxide Nanowire Networks as Effective UV/Vis Photodetection Platforms.

Zhao S, Choi D, Lee T, Boyd AK, Barbara P, Van Keuren E, Hahm JI - J Phys Chem C Nanomater Interfaces (2014)

(a) Typicalphotovoltage acquired from ITO NWs while illuminatingthe device with a 543 nm laser through an optical chopper is shown.(b) Photovoltage signal from SnO2, ZTO, and ZnO nanostructuresis recorded when using the same light source as (a). (c) Typical photovoltagesignal obtained from ITO NW devices when using a 355 nm pulsed laseris provided. The inset is a zoomed-in view with the light on to showclearly the rise time.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4494646&req=5

fig2: (a) Typicalphotovoltage acquired from ITO NWs while illuminatingthe device with a 543 nm laser through an optical chopper is shown.(b) Photovoltage signal from SnO2, ZTO, and ZnO nanostructuresis recorded when using the same light source as (a). (c) Typical photovoltagesignal obtained from ITO NW devices when using a 355 nm pulsed laseris provided. The inset is a zoomed-in view with the light on to showclearly the rise time.
Mentions: The device schematicprovided in Figure 2(a) displays a typicalsample configuration involving networks ofITO NWs. Figure 2(a) also displays a representativevoltage response obtained from ITO NWs, showing a maximum photovoltage(Vph) value of 31 mV. Down (up) arrowsinserted in Figure 2 indicate the time whenthe 543 nm laser directed to the sample is on (off) through a 400Hz chopper wheel. In comparison, Figure 2(b)displays typical photovoltage plots acquired from the other threetypes of devices consisting of SnO2 NWs, ZnO NRs, and ZTONBs. The voltage responses upon illumination on these materials aresignificantly lower than what we observe from ITO NWs. Both ZnO NRand ZTO NB devices result in Vph of ∼3mV, whereas SnO2 NWs produce an even weaker signal of ∼2mV. Although the exact origin of the increased photovoltage responseobserved from ITO NWs in comparison to other nanomaterials is notclear yet, various inherent electrical properties of the materials,such as charge carrier density, resistivity, and carrier mobility,may contribute to this effect. The corresponding values for an ITOthin film, for example, are, respectively, reported to be on the orderof 5 × 1020/cm3, 2 × 10–4 Ω·cm, and 55 cm2/(V·s),12,13 whereas those of a ZnO thin film are 10 × 1019/cm3, 1 × 10–2 Ω·cm, and 35cm2/(V·s).14 The highercharge carrier density and mobility combined with the lower resistivityof ITO may promote the enhanced photoinduced voltage signal in ourexperiment. The magnitude of Vph varieson the same sample devices depending on the laser position. The laserspot is kept on the sample location, producing the highest signalfor all devices characterized in Figure 2.When comparing the highest Vph of thedifferent devices, the photoresponse of ITO NWs is an order of magnitudelarger than other similar semiconducting oxide nanomaterials shownin Figure 2(b). Therefore, herein we focusour discussion of this paper on ITO NWs. The response time of thephotovoltage change of the ITO NW device is determined by using thepulsed Nd:YAG laser as a light source. Figure 2(c) displays the typical response time of the ITO NW photodetectorswhich is defined collectively by the rise (Tr) and decay (Td) time. The responsetime of ITO NW devices is determined as Tr = 20 μs and Td = 1.5 ms.

Bottom Line: The photoresponsivity of the ITO NW devices ranges from 0.07 to 0.2 A/W at a 3 V bias, whose values are in the performance range of most commercial UV/vis photodetectors.Such useful photodetector characteristics from our ITO NW mesh devices are attained straightforwardly without the need for complicated fabrication procedures involving highly specialized lithographic tools.Therefore, our approach of ITO NW network-based photodetectors can serve as a convenient alternative to commercial or single NW-based devices.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Georgetown University , 37th & O Streets NW, Washington, DC 20057, United States ; College of Science, China University of Petroleum , Beijing 102249, People's Republic of China.

ABSTRACT

We demonstrate that indium tin oxide nanowires (ITO NWs) and cationic polymer-modified ITO NWs configured in a network format can be used as high performing UV/vis photodetectors. The photovoltage response of ITO NWs is much higher than similarly constructed devices made from tin oxide, zinc tin oxide, and zinc oxide nanostructures. The ITO NW mesh-based devices exhibit a substantial photovoltage (31-100 mV under illumination with a 1.14 mW 543 nm laser) and photocurrent (225-325 μA at 3 V). The response time of the devices is fast with a rise time of 20-30 μs and a decay time of 1.5-3.7 ms when probed with a 355 nm pulsed laser. The photoresponsivity of the ITO NW devices ranges from 0.07 to 0.2 A/W at a 3 V bias, whose values are in the performance range of most commercial UV/vis photodetectors. Such useful photodetector characteristics from our ITO NW mesh devices are attained straightforwardly without the need for complicated fabrication procedures involving highly specialized lithographic tools. Therefore, our approach of ITO NW network-based photodetectors can serve as a convenient alternative to commercial or single NW-based devices.

No MeSH data available.


Related in: MedlinePlus