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61.
Kyungyea Park Deok‐Kyou Lee Byung‐Sung Kim Haseok Jeon Nae‐Eung Lee Dongmok Whang Hoo‐Jeong Lee Youn Jea Kim Jong‐Hyun Ahn 《Advanced functional materials》2010,20(20):3577-3582
Stretchable and transparent thin film transistors (TFTs) with intrisically brittle oxide semiconductors are built using a wavy structural configuration that can provide high flexibility and stretchability. After device fabrication procedures including high temperature annealing, the oxide semiconductor‐based TFT arrays can be transferred directly to plastic or rubber substrates, without an additional device process, using transfer printing methods. This procedure can avoid some of the thermal degradation problems associated with plastic or rubber substrates by separating them from the annealing procedure needed to improve the device performance. These design and fabrication methods offer the possibility of developing a new format of stretchable electronics. 相似文献
62.
Gd2O3-modified CeO2 particles are prepared by a solid-state reaction method, and are used to remove Pb(II) ions from aqueous solutions by a photoelectrodeposition. The UV–photocatalytic activity for Pb(II) ion removal of the Gd2O3-modified CeO2 is significantly higher than that of pure CeO2. A solid solution Gd0.1Ce0.9O1.95 phase coexisting with the CeO2 matrix phase shows a high ability of photoelectrodeposition for the Pb(II) ions removal, compared to the two-phases mixture of Gd2O3–CeO2. The high photocatalytic activity is also supported by a strong photoluminescence (PL) signal from the Gd0.1Ce0.9O1.95–CeO2. The high activity can be due to a formation of heterojunctions between p-type Gd0.1Ce0.9O1.95 and n-type CeO2, promoting transfer of photogenerated electron–hole pairs and efficiency restraining recombination of the charges. 相似文献
63.
64.
David B. Ahn Won-Yeong Kim Kwon-Hyung Lee Seong-Sun Lee Seung-Hyeok Kim Sodam Park Young-Kuk Hong Sang-Young Lee 《Advanced functional materials》2023,33(18):2211597
Conventional power sources encounter difficulties in achieving structural unitization with complex-shaped electronic devices because of their fixed form factors. Here, it is realized that an on-demand conformal Zn-ion battery (ZIB) on non-developable surfaces uses direct ink writing (DIW)-based nonplanar 3D printing. First, ZIB component (manganese oxide-based cathode, Zn powder-based anode, and UV-curable gel composite electrolyte) inks are designed to regulate their colloidal interactions to fulfill the rheological requirements of nonplanar 3D printing, and establish bi-percolating ion/electron conduction pathways, thereby enabling geometrical synchronization with non-developable surfaces, and ensuring reliable electrochemical performance. The ZIB component inks are conformally printed on arbitrary curvilinear substrates to produce embodied ZIBs that can be seamlessly integrated with complicated 3D objects (including human ears). The conformal ZIB exhibits a high fill factor (i.e., areal coverage of cells on underlying substrates, ≈100%) that ensures high volumetric energy density (50.5 mWh cmcell−3), which exceeds those of previously-reported shape-adaptable power sources. 相似文献
65.
Hai-Yang Chen Zuan-Yu Chen Min Mao Yu-Yue Wu Fan Yang Li-Xiu Gong Li Zhao Cheng-Fei Cao Pingan Song Jie-Feng Gao Guo-Dong Zhang Yong-Qian Shi Kun Cao Long-Cheng Tang 《Advanced functional materials》2023,33(48):2304927
Polydimethylsiloxanes (PDMS) foam as one of next-generation polymer foam materials shows poor surface adhesion and limited functionality, which greatly restricts its potential applications. Fabrication of advanced PDMS foam materials with multiple functionalities remains a critical challenge. In this study, unprecedented self-adhesive PDMS foam materials are reported with worm-like rough structure and reactive groups for fabricating multifunctional PDMS foam nanocomposites decorated with MXene/cellulose nanofiber (MXene/CNF) interconnected network by a facile silicone foaming and dip-coating strategy followed by silane surface modification. Interestingly, such self-adhesive PDMS foam produces strong interfacial adhesion with the hybrid MXene/CNF nano-coatings. Consequently, the optimized PDMS foam nanocomposites have excellent surface super-hydrophobicity (water contact angle of ≈159o), tunable electrical conductivity (from 10−8 to 10 S m−1), stable compressive cyclic reliability in both wide-temperature range (from −20 to 200 oC) and complex environments (acid, sodium, and alkali conditions), outstanding flame resistance (LOI value of >27% and low smoke production rate), good thermal insulating performance and reliable strain sensing in various stress modes and complex environmental conditions. It provides a new route for the rational design and development of advanced PDMS foam nanocomposites with versatile multifunctionalities for various promising applications such as intelligent healthcare monitoring and fire-safe thermal insulation. 相似文献
66.
We propose a self-assembly method for forming large-area high-quality solution-processed titanium oxide (TiO2) films as efficient electron transport layer for organic solar cells. The self-assembled solution-processed TiO2 layers are highly ordered and significantly improved in surface morphology over commonly-used spin-coating process resulting in better charge collection and significant material saving. When incorporated into polymer solar cells, the TiO2 device shows enhanced performance. Furthermore, we demonstrate the TiO2 can form large-area films, and achieve very uniform and improved device performances. Consequently, the self-assembled TiO2 films can be efficient and low-cost electron transport layer potentially for large-area organic optoelectronics. 相似文献
67.
Qing-Dan Yang Tsz-Wai Ng Ming-Fai Lo Ning-Bew Wong Chun-Sing Lee 《Organic Electronics》2012,13(12):3220-3225
Graphene and graphene oxide (GO) have been applied in flexible organic electronic devices with enhanced efficiency of polymeric photovoltaic (OPV) devices. In this work, we demonstrate that storage/operation stability of OPV can be substantially enhanced by spin-coating a GO buffer layer on ITO without any further treatment. With a 2 nm GO buffer layer, the power conversion efficiency (PCE) of a standard copper phthalocyanine (CuPc)/fullerene (C60) based OPV device shows about 30% enhancement from 1.5% to 1.9%. More importantly, while the PCE of the standard device drop to 1/1000 of its original value after 60-days of operation-storage cycles; those of GO-buffered device maintained 84% of initial PCE even after 132-days. Atomic force microscopy studies show that CuPc forms larger crystallites on the GO-buffered ITO substrate leading to better optical absorption and thus photon utilization. Stability enhancement is attributed to the diffusion barrier of the GO layer which slow down diffusion of oxygen species from ITO to the active layers. 相似文献
68.
We have investigated oxynitridation of Si(100) surfaces with nitrous oxide (N2O) gas in a wide range of substrate temperatures (600–1000 °C) and N2O pressures (10−2–102 Pa). The growth rate and atomic composition of the oxynitride layer have been measured by in situ x-ray photoelectron spectroscopy. The surface morphology of the oxynitride layer has been also observed by scanning electron microscopy. The results show that in higher N2O pressure (>1 Pa) regime, the nitridation reaction is suppressed by the oxide layer, which quickly forms on the surface. On the other hand, in lower pressure (<1 Pa) and higher substrate temperature (>900 °C) regime, the nitridation reaction strongly occurs because of the active oxidation (etching reaction), which causes the surface roughness. It is found by argon-ion-sputtering measurements that the nitride layer locally exists only near the surface at the reduced N2O pressure. We discuss qualitatively the oxynitridation kinetics and the effective condition for growing the oxynitride layer. 相似文献
69.
Heterostructured dysprosium vanadate – ZnO for photo-electrocatalytic and self-cleaning applications
In this article, we report fabrication of 5 wt% of Dy as DyVO4 supported ZnO by template-free hydrothermal-thermal decomposition method and its photocatalytic activity towards degradation of azo dyes Rhodamine-B (Rh-B) and Trypan Blue (TB) in solar light, Electrocatalytic activity in methanol oxidation and Self-cleaning properties. The as prepared DyVO4-ZnO was characterized by surface analytical and spectroscopic techniques. The results suggested that Dysprosium vanadate doping on ZnO has increased its photocatalytic efficiency with high reusability. DyVO4-ZnO exhibits higher electrocatalytic activity than prepared ZnO for methanol electrooxidation in alkaline medium, revealing its promising potential as the anode in direct methanol fuel cells. Hydrophobicity of ZnO increases by doping of DyVO4. 相似文献
70.
Improvement in open circuit voltage of n‐ZnO/p‐Si solar cell by using amorphous‐ZnO at the interface
《Progress in Photovoltaics: Research and Applications》2017,25(11):919-927
Several research groups are currently working on n‐ZnO/p‐Si heterojunction solar cell, and recently, Pietruszka et al [Sol. Energ. Mat. Sol. Cells 147 (2016) 164‐170] has reported the highest efficiency of 7.1% for this structure. The main challenge is to enhance the open circuit voltage up to theoretically predicted value of >0.6 V. This paper reports >20% improvement in open circuit voltage of n‐ZnO/p‐Si solar cell by depositing amorphous‐ZnO at the interface at room temperature that possibly improves the passivation and/or avoids oxide formation at the interface during ZnO deposition. Two other materials, aluminum nitride and amorphous‐Si, have also been used as buffer layers to evaluate their effect on suppression of interface states. Furthermore, additional advantage of ZnO as an antireflector has been experimentally verified for different thicknesses of ZnO film. 相似文献