- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Transparent Conductive Materials (Materials, Synthesis, Characterization, Applications) || Graphene
摘要： Graphene regards to a monolayer of carbon atoms arranged in a ?at two-dimensional (2D) honeycomb lattice. It belongs to the family of carbon nanostructures that have won two Nobel Prizes and have been the focus of intensive research and development in the past few decades with well-known members including zero-dimensional (0D) fullerenes (or bucky-balls), one-dimensional (1D) carbon nanotubes, and three-dimensional (3D) graphite as illustrated in Figure 3.2.1. Since its discovery in 2004, graphene has attracted enormous interest due to its superior physical properties including high charge carrier mobility, optical transparency, ?exibility, and chemical stability. The intrinsic graphene has a zero energy bandgap, Eg, which has prevented it to be used in a similar way to the conventional semiconductors of well-de?ned Eg. However, the low charge carrier density and high charge mobility in graphene imply that graphene can be an excellent transparent conductor (TC) with both high electrical conductivity and optical transparency. Therefore, graphene makes an excellent alternative to transparent conducting oxides (TCOs) demanded for a large variety of photonic and optoelectronic applications including ?exible displays, light-emitting devices, detectors, touch screens, transistors, electromechanical resonators, ultracapacitors, and photovoltaics (PVs).
关键词： Photovoltaics,Optoelectronics,Graphene,Transparent Conductors,Chemical Vapor Deposition
更新于2025-09-23 15:21:21
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Pulsed-grown graphene for flexible transparent conductors
摘要： In the race to find novel transparent conductors for next-generation optoelectronic devices, graphene is supposed to be one of the leading candidates, as it has the potential to satisfy all future requirements. However, the use of graphene as a truly transparent conductor remains a great challenge because its lowest sheet resistance demonstrated so far exceeds that of the commercially available indium tin oxide. The possible cause of low conductivity lies in its intrinsic growth process, which requires further exploration. In this work, I have approached this problem by controlling graphene nucleation during the chemical vapor deposition process as well as by adopting three distinct procedures, including bis(trifluoromethanesulfonyl)amide doping, post annealing, and flattening of graphene films. Additionally, van der Waals stacked graphene layers have been prepared to reduce the sheet resistance effectively. I have demonstrated an efficient and flexible transparent conductor with the extremely low sheet resistance of 40 Ω sq?1, high transparency (Tr ≈90%), and high mechanical flexibility, making it suitable for electrode materials in future optoelectronic devices.
关键词： doping,flexibility,chemical vapor deposition,graphene,transparent conductors,sheet resistance
更新于2025-09-19 17:15:36
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Flexible, multifunctional nanoribbon arrays of palladium nanoparticles for transparent conduction and hydrogen detection
摘要： A novel combination of nanostructuring techniques is undertaken to obtain a multifunctional material system consisting of planar arrays of nanoribbons of Pd nanoparticles (NPs) on polyethylene terephthalate (PET) substrates. The first stage was to prepare a laser-induced periodic surface structure (LIPSS) on the PET substrate, which electron microscopy revealed to be a large area, high coherence nanoripple pattern with spacing of (204 ± 1) nm and amplitude of (46 ± 9) nm. The second stage comprised NP (diameter 5 nm) deposition by orientating the nanostructured substrate to a Pd NP beam from a sputter gas phase aggregation source such that the substrate was partially shadowed by the ripple pattern (the incident angle with respect to the normal of the PET substrate was varied between 60 and 75o). This resulted in the formation of an array of NP ribbons (thickness ? 20 nm) on the ripple ridges, the mean ribbon width depending on the deposition incidence angle, thus confirming the shadowing effect. These planar arrays were studied as candidates for both flexible, transparent conductors and hydrogen sensors. Analysis of optical transmittance indicates that a mean inter-ribbon gap of above 100 nm is required in order to improve the average transmittance beyond 80 %. Four-probe electrical resistance measurements show these nanoribbon arrays to be electrically anisotropic structures whose sheet resistance is understood to be governed by the contact resistance between NPs. An additional functionality is proven for the fabricated substrates: reversible detection of hydrogen at a partial pressure above ? 60 ppm, with good electrical sensitivity in the dilute (?-hydride) regime.
关键词： palladium,Laser Induced Periodic Surface Structures,oblique deposition,nanoparticles,transparent conductors,hydrogen detection
更新于2025-09-10 09:29:36
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3D stretchable and transparent conductors with controllable strain-distribution based on template-assisted transfer printing
摘要： Although stretchable transparent conductors, stemmed from the strategies of both conductive composite and structural design of non-stretchable conductors, have been extensively studied, these conductors either suffer from a low stretchability or require a complex fabrication process, which drastically limits their practical applications. Here, we propose a novel strategy combining the design of substrates and a simple template-assisted transfer printing process to fabricate 3D transparent conductors. The strategy not only eliminates the complex and costly fabrication processes, but it also endows conductors with high stretchability and long-term stability thanks to the controllable strain-distribution as well as the seamless connection between the conductor layer and the substrate. These newly-designed 3D conductors achieve a low sheet resistance of 1.0 Ω/sq with a high transmittance of above 85% and remain stable without obvious resistance change during 1000 stretching-relaxation cycles until 60% strain, which are superior to most reported conductors. A large-area stretchable heater based on the 3D conductor realizes the temperature fluctuation below 10% even under a large strain, thus showing huge application prospects in the field of wearable healthcare electronics. The simple solution-processed fabrication method and high performance such as stretchability and low resistance change over large strain range promote the practical applications of these newly-designed 3D conductors.
关键词： 3D substrates,template-assisted transfer printing,solution-processed,wearable electronics,stretchable transparent conductors
更新于2025-09-04 15:30:14