19 research outputs found
Quantum dots for hybrid energy harvesting: from integration to piezo-phototronics
Energy harvesting, which converts wasted environmental energy into electricity by utilizing various physical effects, hasattracted tremendous research interests as is one of the key technologies to realize advanced electronics in the future. In this review, we introduce recent progress in the field of hybrid energy harvesting technology. In particular, we focus on a quantum dots (QD)‐based hybrid energy harvesting device. Attributed to fascinating material properties that QD possess, employment of QDs into hybrid energy harvesting has shown great potential for independent and sustainable energy supply.First, an integration of a QD solar cell into a mechanical energy harvester is discussed to harness different types of environmental energy sources simultaneously. Second, a comprehensive explanation of a piezotronic and piezo‐phototronic effect is provided, which is followed by QD‐based piezo‐phototronic applications. Finally, we summarize recent progress that has been made in energy harvesting technology involving a photovoltaic and piezo/triboelectric effec
Consecutive Junction-Induced Efficient Charge Separation Mechanisms for High-Performance MoS2/Quantum Dot Phototransistors.
Phototransistors that are based on a hybrid vertical heterojunction structure of two-dimensional (2D)/quantum dots (QDs) have recently attracted attention as a promising device architecture for enhancing the quantum efficiency of photodetectors. However, to optimize the device structure to allow for more efficient charge separation and transfer to the electrodes, a better understanding of the photophysical mechanisms that take place in these architectures is required. Here, we employ a novel concept involving the modulation of the built-in potential within the QD layers for creating a new hybrid MoS2/PbS QDs phototransistor with consecutive type II junctions. The effects of the built-in potential across the depletion region near the type II junction interface in the QD layers are found to improve the photoresponse as well as decrease the response times to 950 μs, which is the faster response time (by orders of magnitude) than that recorded for previously reported 2D/QD phototransistors. Also, by implementing an electric-field modulation of the MoS2 channel, our experimental results reveal that the detectivity can be as large as 1 × 1011 jones. This work demonstrates an important pathway toward designing hybrid phototransistors and mixed-dimensional van der Waals heterostructures.The research leading to these results has received funding from
the European Research Council under the European Union’s Seventh Framework Programme (FP/2007−2013)/ERC
Grant Agreement no. 340538. This work was also supported
by the National Research Foundation of Korea (NRF)
(2015M2A2A6A02045252) and Samsung Global Research
Outreach (Samsung GRO) program. In addition, S.M.M.
would like to thank The Royal Society for financial support
Truly form-factor–free industrially scalable system integration for electronic textile architectures with multifunctional fiber devices
Funding Information: This work was supported by the European Commission (H2020, 1D-NEON, grant agreement ID: 685758). J.M.K. and L.G.O. acknowledge the support from the U.K. Research and Innovation (EPSRC, EP/P027628/1). We thank Y. Bernstein and J. Faulkner for helping with grammar check. Funding Information: Acknowledgments Funding:ThisworkwassupportedbytheEuropeanCommission(H2020,1D-NEON,grant agreementID:685758).J.M.K.andL.G.O.acknowledgethesupportfromtheU.K.Researchand Innovation(EPSRC,EP/P027628/1).W ethankY .BernsteinandJ.Faulknerforhelpingwith grammarcheck.Authorcontributions:S.L.andJ.M.K.conceivedtheproject.S.L.,L.G.O.,P .B., R.Martins,andJ.M.K.supervisedtheproject.S.L.andH.L.developedF-PD.S.L.,Y .-W .L., G.-H.A., D.-W .S., J.I.S.,andS.C.developedF-SC.C.L.F ., A.S.,R.I.,P .B., andR.Martinsdevelopedfiber transistor.S.L.,H.L.,andS.C.developedF-LED.ThefiberdeviceswereevaluatedbyS.L.,H.W .C., D.-W .S., H.L.,S.J.,S.D.H.,S.Y .B., S.Z.,W .H.-C., Y .-H.S., X.-B.F ., T .H.L., J.-W .J., andY .K. The developmentofweavingprocesswasconductedbyS.L.,H.W .C., F .M.M., P .J., andV .G.C. Thelaser interconnectionwasdevelopedbyS.L.,H.W .C., K.U.,M.E.,andM.S.Thetextiledemonstrations werecharacterizedbyS.L.,H.W .C., D.-W .S., J.Y ., S.S.,U.E.,S.N.,A.C.,A.M.,R.Momentè,J.G.,N.D., S.M.,C.-H.K.,M.L.,A.N.,D.J.,M.C.,andY .C. ThismanuscriptwaswrittenbyS.L.andJ.M.K.and reviewed by H.W .C., D.-W .S., M.C.,L.G.O., P .B., E.F ., and G.A.J.A. All authors discussed the results andcommentedonthemanuscript.Competinginterests:Theauthorsdeclarethattheyhave nocompetinginterests.Dataandmaterialsavailability:Alldataneededtoevaluatethe conclusionsinthepaperarepresentinthepaperand/ortheSupplementaryMaterials. Publisher Copyright: Copyright © 2023 The Authors, some rights reserved.An integrated textile electronic system is reported here, enabling a truly free form factor system via textile manufacturing integration of fiber-based electronic components. Intelligent and smart systems require freedom of form factor, unrestricted design, and unlimited scale. Initial attempts to develop conductive fibers and textile electronics failed to achieve reliable integration and performance required for industrial-scale manufacturing of technical textiles by standard weaving technologies. Here, we present a textile electronic system with functional one-dimensional devices, including fiber photodetectors (as an input device), fiber supercapacitors (as an energy storage device), fiber field-effect transistors (as an electronic driving device), and fiber quantum dot light-emitting diodes (as an output device). As a proof of concept applicable to smart homes, a textile electronic system composed of multiple functional fiber components is demonstrated, enabling luminance modulation and letter indication depending on sunlight intensity.publishersversionpublishe
Quantum Dots for Hybrid Energy Harvesting: From Integration to Piezo‐Phototronics
Energy harvesting, which converts wasted environmental energy into electricity by utilizing various physical effects, hasattracted tremendous research interests as is one of the key technologies to realize advanced electronics in the future. In this review, we introduce recent progress in the field of hybrid energy harvesting technology. In particular, we focus on a quantum dots (QD)‐based hybrid energy harvesting device. Attributed to fascinating material properties that QD possess, employment of QDs into hybrid energy harvesting has shown great potential for independent and sustainable energy supply.First, an integration of a QD solar cell into a mechanical energy harvester is discussed to harness different types of environmental energy sources simultaneously. Second, a comprehensive explanation of a piezotronic and piezo‐phototronic effect is provided, which is followed by QD‐based piezo‐phototronic applications. Finally, we summarize recent progress that has been made in energy harvesting technology involving a photovoltaic and piezo/triboelectric effec
Improved Ionic Diffusion through the Mesoporous Carbon Skin on Silicon Nanoparticles Embedded in Carbon for Ultrafast Lithium Storage
Because of their
combined effects of outstanding mechanical stability,
high electrical conductivity, and high theoretical capacity, silicon
(Si) nanoparticles embedded in carbon are a promising candidate as
electrode material for practical utilization in Li-ion batteries (LIBs)
to replace the conventional graphite. However, because of the poor
ionic diffusion of electrode materials, the low-grade ultrafast cycling
performance at high current densities remains a considerable challenge.
In the present study, seeking to improve the ionic diffusion, we propose
a novel design of mesoporous carbon skin on the Si nanoparticles embedded
in carbon by hydrothermal reaction, poly(methyl methacrylate) coating
process, and carbonization. The resultant electrode offers a high
specific discharge capacity with excellent cycling stability (1140
mA h g<sup>–1</sup> at 100 mA g<sup>–1</sup> after 100
cycles), superb high-rate performance (969 mA h g<sup>–1</sup> at 2000 mA g<sup>–1</sup>), and outstanding ultrafast cycling
stability (532 mA h g<sup>–1</sup> at 2000 mA g<sup>–1</sup> after 500 cycles). The battery performances are surpassing the previously
reported results for carbon and Si composite-based electrodes on LIBs.
Therefore, this novel approach provides multiple benefits in terms
of the effective accommodation of large volume expansions of the Si
nanoparticles, a shorter Li-ion diffusion pathway, and stable electrochemical
conditions from a faster ionic diffusion during cycling
Tunneled Mesoporous Carbon Nanofibers with Embedded ZnO Nanoparticles for Ultrafast Lithium Storage
Carbon and metal
oxide composites have received considerable attention
as anode materials for Li-ion batteries (LIBs) owing to their excellent
cycling stability and high specific capacity based on the chemical
and physical stability of carbon and the high theoretical specific
capacity of metal oxides. However, efforts to obtain ultrafast cycling
stability in carbon and metal oxide composites at high current density
for practical applications still face important challenges because
of the longer Li-ion diffusion pathway, which leads to poor ultrafast
performance during cycling. Here, tunneled mesoporous carbon nanofibers
with embedded ZnO nanoparticles (TMCNF/ZnO) are synthesized by electrospinning,
carbonization, and postcalcination. The optimized TMCNF/ZnO shows
improved electrochemical performance, delivering outstanding ultrafast
cycling stability, indicating a higher specific capacity than previously
reported ZnO-based anode materials in LIBs. Therefore, the unique
architecture of TMCNF/ZnO has potential for use as an anode material
in ultrafast LIBs
Carbon-Encapsulated Hollow Porous Vanadium-Oxide Nanofibers for Improved Lithium Storage Properties
Carbon-encapsulated
hollow porous vanadium-oxide (C/HPV<sub>2</sub>O<sub>5</sub>) nanofibers
have been fabricated using electrospinning and postcalcination. By
optimized postcalcination of vanadium-nitride and carbon-nanofiber
composites at 400 °C for 30 min, we synthesized a unique architecture
electrode with interior void spaces and well-defined pores as well
as a uniform carbon layer on the V<sub>2</sub>O<sub>5</sub> nanofiber
surface. The optimized C/HPV<sub>2</sub>O<sub>5</sub> electrode postcalcined
at 400 °C for 30 min showed improved lithium storage properties
with high specific discharge capacities, excellent cycling durability
(241 mA h g<sup>–1</sup> at 100 cycles), and improved high-rate
performance (155 mA h g<sup>–1</sup> at 1000 mA g<sup>–1</sup>), which is the highest performance in comparison with previously
reported V<sub>2</sub>O<sub>5</sub>-based cathode materials. The improved
electrochemical feature is due to the attractive properties of the
carbon-encapsulated hollow porous structure: (I) excellent cycling
durability with high specific capacity relative to the adoption of
carbon encapsulation as a physical buffer layer and the effective
accommodation of volume changes due to the hollow porous structure,
(II) improved high-rate performance because of a shorter Li-ion diffusion
pathway resulting from interior void spaces and well-defined pores
at the surface. This unique electrode structure can potentially provide
new cathode materials for high-performance lithium-ion batteries