A tunable colloidal quantum dot photo field-effect transistor

Ghosh, Subir; Hoogland, Sjoerd; Sukhovatkin, Vlad; Levina, Larissa; Sargent, Edward H.

doi:10.1063/1.3636438

Cited by 19 publications

(22 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In order to investigate the photoresponse performance, a particular 530/980 nm light was chosen for our measurements. Figure 3 PbS-QDs [31] Ethanedithiol (EDT) 1 × 10 −4 PbS-QDs [32] Aluminum-doped zinc oxide (AZO) >5/> 5 s PbS-QDs [33] EDT 8 × 10 −3 PbS-QDs [34] Graphene 0.3/1.7 s Inert atmosphere PbS-QDs [35] Ammonium thiocyanate (SCN) 0.04 PbS-QDs [4] Carbon nanotubes 0.8/0.2 ms Inert atmosphere PbSe-QDs [36] Hydrazine 1.2 Au-PbS QDs [37] Hydrazine >1/>10 ms N 2 wileyonlinelibrary.com www.particle-journal.com www.MaterialsViews.com intensity, implying a higher EQE can be obtained at 530 nm, consistent with the wavelength-dependent EQE (Figure 3 a). The time-dependent photoresponse was also measured by turning light on and off periodically at an applied bias of V (AB) = 5 V. This result is shown in Figure 3 c, where the device exhibited higher sensitivity and stability to visible (530 nm) and nearinfrared (980 nm) light.…”

Section: Resultsmentioning

confidence: 99%

Ultrasensitive PbS‐Quantum‐Dot Photodetectors for Visible–Near‐Infrared Light Through Surface Atomic‐Ligand Exchange

Wang

et al. 2015

Part & Part Syst Charact

View full text Add to dashboard Cite

properties and potential applications, these devices often show a poor response time or low sensitivity. [ 11 ] The main reasons can be the limited conductivity and carrier mobility of the QDs, which are too low to meet the requirements of high performance. To passivate the surfaces, QDs are generally capped by long-chain organic ligands, which will cause certain interparticle spacings between individual QDs, and accordingly infl uence the charge carrier mobility and conductivity. [ 12 ] Several strategies have been used to enhance the carrier transfer, and thus to enable the applications of QD-based PDs in microelectronics and optoelectronics. To form a fi lm capable of electronic transport, QDs are usually treated using short organic ligands with characteristic functional groups (e.g., dithiols) to exchange long hydrocarbon ligands (e.g., oleic acid), [ 13 ] but they produce short barriers between the QDs that also militate against effi cient carrier transport when processed into fi lms. In photovoltaic devices, some inorganic ligands, such as tetrabutylammonium bromide (TBAB), have led to impressive conductive transfer, unlike organic ligands, which greatly enhances the performance of such QDs. [ 14,15 ] Lead sulfi de (PbS) QDs show a high potential applicability for high-performing photovoltaic (PV) and photoconductive devices attributed to two advantages over other materials. [ 4 ] First, the quantum confi nement-induced tunability of their bandgap over an energy range is as wide as 0.4-2 eV. Second, it has a multiple exciton generation (MEG) capability. [16][17][18][19] A direct implication is that the PbS-QDs are capable of broadband photoresponse from visible light to the infrared. However, PbSQDs are generally capped by organic ligands, which employ long chains (8-18 carbons) to ensure the stability of QDs in solution. [ 20 ] As an adverse effect, this becomes a determining factor for the high resistive nature of QDs, and impacts their charge carrier mobility and conductivity when processed into fi lms. [ 14 ] In addition, detection must be operated in inert atmosphere even though organic ligands have the ability of protecting oxidation-prone QDs surface. [ 21 ] Therefore, new ligand strategies that minimize interparticle spacing and are immune to oxidative attack are required for construction of high-performance

show abstract

Section: Resultsmentioning

confidence: 99%

Ultrasensitive PbS‐Quantum‐Dot Photodetectors for Visible–Near‐Infrared Light Through Surface Atomic‐Ligand Exchange

Wang

et al. 2015

Part & Part Syst Charact

View full text Add to dashboard Cite

show abstract

“…In quantum dots an effective bandgap can also be tuned for specific applications simply by controlling the size of the dots [214], and their electrical transport properties can be further engineered by functionalizing the surface of the dots. Solution-processed QDs have been used as the photoactive layers in non-graphene devices for light emission [215], photovoltaics [216] and photodetection [217][218][219], and have recently appeared in consumer products such as ultra-bright television screens.…”

Section: Engineering the Optoelectronic Properties Of Graphene By Funmentioning

confidence: 99%

Properties and applications of chemically functionalized graphene

Craciun

Khrapach

Barnes

et al. 2013

J. Phys.: Condens. Matter

102

View full text Add to dashboard Cite

The vast and yet largely unexplored family of graphene materials has great potential for future electronic devices with novel functionalities. The ability to engineer the electrical and optical properties in graphene by chemically functionalizing it with a molecule or adatom is widening considerably the potential applications targeted by graphene. Indeed, functionalized graphene has been found to be the best known transparent conductor or a wide gap semiconductor. At the same time, understanding the mechanisms driving the functionalization of graphene with hydrogen is proving to be of fundamental interest for energy storage devices. Here we discuss recent advances on the properties and applications of chemically functionalized graphene.

show abstract

“…Colloidal quantum dots (CQDs) are known to have outstanding optical and electrical properties, which has led to extensive studies of next generation optoelectronic devices such as light emitting diode, photodetectors, field effect transistors, and photovoltaics. 1 − 7 In particular, the CQD’s tunable bandgap has the potential to cover the entire solar spectrum and harness photon energies more efficiently compared to conventional solar cell. 8 − 10 To date, device efficiency improvements have been achieved by surface ligand engineering, substitution doping and/or multijunction device architectures.…”

Section: Introductionmentioning

confidence: 99%

High Performance PbS Quantum Dot/Graphene Hybrid Solar Cell with Efficient Charge Extraction

Kim

Neo

Hou

et al. 2016

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Hybrid colloidal quantum dot (CQD) solar cells are fabricated from multilayer stacks of lead sulfide (PbS) CQD and single layer graphene (SG). The inclusion of graphene interlayers is shown to increase power conversion efficiency by 9.18%. It is shown that the inclusion of conductive graphene enhances charge extraction in devices. Photoluminescence shows that graphene quenches emission from the quantum dot suggesting spontaneous charge transfer to graphene. CQD photodetectors exhibit increased photoresponse and improved transport properties. We propose that the CQD/SG hybrid structure is a route to make CQD thin films with improved charge extraction, therefore resulting in improved solar cell efficiency.

show abstract

A tunable colloidal quantum dot photo field-effect transistor

Abstract: Articles you may be interested inProbing the structural dependency of photoinduced properties of colloidal quantum dots using metal-oxide photoactive substrates

Cited by 19 publications

References 8 publications

Ultrasensitive PbS‐Quantum‐Dot Photodetectors for Visible–Near‐Infrared Light Through Surface Atomic‐Ligand Exchange

Ultrasensitive PbS‐Quantum‐Dot Photodetectors for Visible–Near‐Infrared Light Through Surface Atomic‐Ligand Exchange

Properties and applications of chemically functionalized graphene

High Performance PbS Quantum Dot/Graphene Hybrid Solar Cell with Efficient Charge Extraction

Contact Info

Product

Resources

About