scholarly journals Simultaneous Improvement in the Corrosion Resistance and Visible Transparency of ZnO/Cu/ZnO Transparent Heaters with Reactively Sputtered Al2O3 Layers

2021 ◽  
Vol 59 (3) ◽  
pp. 155-161
Author(s):  
Geumhyuck Bang ◽  
Dooho Choi
Keyword(s):  
Corrosion Resistance ◽  
Visible Light ◽  
Sheet Resistance ◽  
Optical Transmittance ◽  
Light Transmittance ◽  
Resistance Change ◽  
Al2o3 Layer ◽  
Resistance Increase ◽  
Effective Moisture ◽  
20 Nm

In this study, we report a methodology that simultaneously improved the corrosion resistance and visible transparency of ZnO/Cu/ZnO transparent heaters with the addition of reactively sputtered Al2O3 layers. To assess corrosion resistance, ZnO and Al2O3 layers with thicknesses in the range of 0-20 nm were deposited onto 20 nm-thick Cu layer, and the corrosion behavior of the underlying Cu layers was investigated by evaluating the sheet resistance change in an 85 °C/85% humidity test. While the 20 nm-thick ZnO layer was not an effective moisture barrier, showing a sheet resistance increase of more than 50% after 10,000 m, the sheet resistance of the Cu layer below the 5 nm-thick Al2O3 layer did not show an observable increase for equal duration. Optical transmittance was also investigated by constructing glass/ZnO/Cu/ZnO/Al2O3 structures with varying thicknesses for the top ZnO and Al2O3 layers, in the range of 10-30 and 10-60 nm, respectively The thicknesses of the bottom ZnO and Cu layers were fixed at 30 nm and 10 nm. The results revealed that the average visible light transmittance of the ZnO/Cu/ZnO/Al2O3 structure increased by 2.5% over the optimized ZnO/Cu/ZnO structure.

scholarly journals Fabrication of Semi-transparent W film Heaters via Phase Transformation

2021 ◽  
Vol 59 (9) ◽  
pp. 664-669
Author(s):  
Jiyun Choi ◽  
Dooho Choi
Keyword(s):  
Sheet Resistance ◽  
Joule Heating ◽  
Optical Transmittance ◽  
High Resistivity ◽  
Heating Process ◽  
X Ray Diffraction ◽  
Β Phase ◽  
Α Phase ◽  
20 Nm ◽  
Heater Current

In this study, we prepared highly thermostable semi-transparent heaters composed of W layers with thicknesses of 1-20 nm, on which a 30 nm-thick ZnO layer was deposited to serve as an anti-oxidation barrier. The optical transmittance and sheet resistance of the heaters could be greatly modulated by varying the W layer thickness. For layer thicknesses up to 10 nm, the initial Joule heating above 100 oC significantly reduced the sheet resistance, by 300% for a 6 nm-thick W layer at a fixed voltage for a duration of 400 s. During the test period, heater current and heating capability continuously increased. In subsequent heater operations, the heaters exhibited highly reproducible heating capability. In contrast, for films thicker than 10 nm, the Joule heating process resulted in only a marginal reduction in sheet resistance, i.e., by 4% for a 20 nm-thick W layer. In order to investigate the sharp dependence of heater characteristics on thickness, we performed x-ray diffraction analyses, which revealed that the films thinner than 10 nm were composed of both the equilibrium low-resistivity α-phase and metastable high-resistivity β-phase, and films thicker than 10 nm contained mostly α-phase. The Joule heating process for the thinner films was found to transform the β-phase into α-phase at temperatures above 100 oC, which resulted in significant improvement in the heating capability of the 6 nm-thick W layer. For films thicker than 10 nm, the W layers contained mostly α-phase and no such transformation-induced effects were observed. Finally, W heaters composed of α-phase exhibited highly thermostable and reproducible heater properties, which make the heaters suitable for applications with semi-transparent heaters.

scholarly journals The Transmittance Modulation of ZnO/Cu/ZnO Transparent Conductive Electrodes Prepared on Glass Substrates

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 3916
Author(s):  
Dooho Choi
Keyword(s):  
Visible Light ◽  
Sheet Resistance ◽  
High Performance ◽  
Critical Role ◽  
Optoelectronic Devices ◽  
Light Transmittance ◽  
Glass Substrates ◽  
Average Transmittance ◽  
Optimized Conditions

With the explosive development of optoelectronic devices, the need for high-performance transparent conductive (TCE) electrodes for optoelectronic devices has been increasing accordingly. The two major TCE requirements are (1) visible light average transmittance higher than 80% and (2) sheet resistance lower than 10 Ω/sq. In this study, we investigated the critical role of the top and bottom ZnO thicknesses for the ZnO/Cu/ZnO electrodes prepared on glass substrates. It was shown that the required Cu thickness to meet the conductivity requirement is 8 nm, which was fixed and then the thicknesses of the top and ZnO layers were independently varied to experimentally determine the optimized conditions for optical transparency. The thicknesses of the top and bottom ZnO layers were both found to significantly affect the peak transmittance as well as the average visible light transmittance. The ZnO/Cu/ZnO electrode exhibits peak and average transmittance of 95.4% and 87.4%, excluding the transmittance of glass substrates, along with a sheet resistance of 9.7 Ω/sq, with a corresponding Haacke’s figure of merit (φH=Tave10Rs) of 0.064, which exceeds the reported value for the ZnO/Cu/ZnO electrodes, manifesting the need of experimental optimization in this study.

The Origin of Corrosion Resistance Change Induced by Sn and Nb Alloying in Zr Alloys

2020 ◽  
Author(s):  
Rong Yuan ◽  
Xie Yao-Ping ◽  
Tong Li ◽  
Chen-Hao Xu ◽  
Mei-Yi Yao ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Resistance Change ◽  
Nb Alloying ◽  
Zr Alloys

scholarly journals Windblown Sand-Induced Degradation of Glass Panels in Curtain Walls

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 607
Author(s):  
Yuxi Zhao ◽  
Rongcheng Liu ◽  
Fan Yan ◽  
Dawei Zhang ◽  
Junjin Liu
Keyword(s):  
Visible Light ◽  
Mass Loss ◽  
Effective Area ◽  
Area Ratio ◽  
Light Transmittance ◽  
Relative Mass ◽  
Impact Time ◽  
Windblown Sand ◽  
Glass Panels ◽  
The Impact

The windblown sand-induced degradation of glass panels influences the serviceability and safety of these panels. In this study, the degradation of glass panels subject to windblown sand with different impact velocities and impact angles was studied based on a sandblasting test simulating a sandstorm. After the glass panels were degraded by windblown sand, the surface morphology of the damaged glass panels was observed using scanning electron microscopy, and three damage modes were found: a cutting mode, smash mode, and plastic deformation mode. The mass loss, visible light transmittance, and effective area ratio values of the glass samples were then measured to evaluate the effects of the windblown sand on the panels. The results indicate that, at high abrasive feed rates, the relative mass loss of the glass samples decreases initially and then remains steady with increases in impact time, whereas it increases first and then decreases with an increase in impact angle such as that for ductile materials. Both visible light transmittance and effective area ratio decrease with increases in the impact time and velocities. There exists a positive linear relationship between the visible light transmittance and effective area ratio.

Width-dependent anomalous CoSix sheet resistance change by Ti and TiN capping process

2006 ◽  
Vol 498 (1-2) ◽  
pp. 282-285 ◽  
Author(s):  
Yen-Ming Chen ◽  
George C. Tu ◽  
Ying-Lang Wang
Keyword(s):  
Sheet Resistance ◽  
Resistance Change

scholarly journals Problems and Prospects of Nanometer Transparent Infrared Thermal Insulation Glass

2018 ◽  
Vol 53 ◽  
pp. 01013
Author(s):  
Nan Zhang ◽  
Mengyuan Xu ◽  
Ning Li
Keyword(s):  
Energy Conservation ◽  
Visible Light ◽  
Energy Saving ◽  
Building Energy ◽  
Light Transmittance ◽  
Large Area ◽  
Existing Building ◽  
Economic Application ◽  
Performance Indexes ◽  
Building Energy Saving

The existing building energy-saving reconstruction has a large area in our country. If the performance indexes such as the shading coefficient, visible light transmittance and hardness of the coating heat-insulating glass are in the condition of reaching the specification, and it can meet the needs of energy conservation and reform in building, it is a suitable technology for economic application.

Monoclinic oxygen-deficient tungsten oxide nanowires for dynamic and independent control of near-infrared and visible light transmittance

2018 ◽  
Vol 5 (2) ◽  
pp. 291-297 ◽  
Author(s):  
Shengliang Zhang ◽  
Sheng Cao ◽  
Tianran Zhang ◽  
Qiaofeng Yao ◽  
Adrian Fisher ◽  
...  
Keyword(s):  
Visible Light ◽  
Tungsten Oxide ◽  
Near Infrared ◽  
Underlying Mechanism ◽  
Single Component ◽  
Light Transmittance ◽  
Independent Control ◽  
Oxide Nanowires ◽  
Electrochromic Material

Independent control of near-infrared and visible light using a single-component electrochromic material and its underlying mechanism are demonstrated.

Size-Dependent Effect of Cu2O Nanocubes in Electrochemical and Photocatalytic Properties

2018 ◽  
Vol 18 (12) ◽  
pp. 8282-8288 ◽  
Author(s):  
Yuanyuan Tang ◽  
Yinlong Xu ◽  
Caiyu Qi ◽  
Xianyang Li ◽  
Enming Xing ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Visible Light ◽  
Electrochemical Impedance ◽  
Linear Sweep Voltammetry ◽  
Absorption Capacity ◽  
Electrochemical Impedance Spectra ◽  
Size Dependent ◽  
Eis Measurements ◽  
20 Nm ◽  
Degradation Of Methyl Orange

Cu2O nanocubes with different size (ranging from 20 nm to 400 nm) were prepared by a seed-mediated method to systematically explore the strong size-dependent properties in photocatalytic degradation of methyl orange (MO). Cu2O nanotubes were characterized by TEM, XRD, UV-Vis measurements. The size-dependent photocatalytic efficiency of the Cu2O nanocubes was evaluated by degradation of methyl orange (MO) in water under visible light (λ > 420 nm) irradiation. Furthermore, the photocurrent, linear sweep voltammetry (LSV) and electrochemical impedance spectra (EIS) measurements were applied to elucidate the size-dependent properties of Cu2O nanocubes, which demonstrated that smaller Cu2O nanocubes with certain length (30 nm) showed higher current density, faster electron transfer and lower rate of charge recombination in their exposed (100) facet. Therefore, 30 nm Cu2O nanocubes showed stronger visible light absorption capacity and higher photocatalytic activity in MO degradation among a series of nanocubes (20, 30, 100, 130, 200 and 400 nm) and their corresponding photocatalytic activities decreased with increasing the particles sizes.

scholarly journals Resistance Reduction of Conductive Patterns Printed on Textile by Curing Shrinkage of Passivation Layers

Micromachines ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 539 ◽  
Author(s):  
Tomoya Koshi ◽  
Ken-ichi Nomura ◽  
Manabu Yoshida
Keyword(s):  
Induced Resistance ◽  
Tensile Deformation ◽  
Curing Temperature ◽  
Electronic Textiles ◽  
Resistance Change ◽  
Resistance Increase ◽  
Resistance Reduction ◽  
Passivation Layers ◽  
Curing Shrinkage ◽  
Initial Resistance

Directly printing conductive ink on textiles is simple and compatible with the conventional electronics manufacturing process. However, the conductive patterns thus formed often show high initial resistance and significant resistance increase due to tensile deformation. Achieving conductive patterns with low initial resistance and reduced deformation-induced resistance increase is a significant challenge in the field of electronic textiles (e-textiles). In this study, the passivation layers printed on conductive patterns, which are necessary for practical use, were examined as a possible solution. Specifically, the reduction of the initial resistance and deformation-induced resistance increase, caused by the curing shrinkage of passivation layers, were theoretically and experimentally investigated. In the theoretical analysis, to clarify the mechanism of the reduction of deformation-induced resistance increase, crack propagation in conductive patterns was analyzed. In the experiments, conductive patterns with and without shrinking passivation layers (polydimethylsiloxane) cured at temperatures of 20–120 °C were prepared, and the initial resistances and resistance increases due to cyclic tensile and washing in each case were compared. As a result, the initial resistance was reduced further by the formation of shrinking passivation layers cured at higher temperatures, and reduced to 0.45 times when the curing temperature was 120 °C. The cyclic tensile and washing tests confirmed a 0.48 and a 0.011 times reduction of resistance change rate after the 100th elongation cycle (10% in elongation rate) and the 10th washing cycle, respectively, by comparing the samples with and without shrinking passivation layers cured at 120 °C.

scholarly journals Development of a Cr-Ni-V-N Medium Manganese Steel with Balanced Mechanical and Corrosion Properties

Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 705 ◽  
Author(s):  
Tarek Allam ◽  
Xiaofei Guo ◽  
Simon Sevsek ◽  
Marta Lipińska-Chwałek ◽  
Atef Hamada ◽  
...  
Keyword(s):  
Grain Size ◽  
Stainless Steel ◽  
Corrosion Resistance ◽  
Twip Steel ◽  
Total Elongation ◽  
Manganese Steel ◽  
Ultrafine Grain ◽  
Corrosion Properties ◽  
Hot Rolled ◽  
20 Nm

A novel medium manganese (MMn) steel with additions of Cr (18%), Ni (5%), V (1%), and N (0.3%) was developed in order to provide an enhanced corrosion resistance along with a superior strength–ductility balance. The laboratory melted ingots were hot rolled, cold rolled, and finally annealed at 1000 °C for 3 min. The recrystallized single-phase austenitic microstructure consisted of ultrafine grains (~1.3 µm) with a substantial amount of Cr- and V-based precipitates in a bimodal particle size distribution (100–400 nm and <20 nm). The properties of the newly developed austenitic MMn steel X20CrNiMnVN18-5-10 were compared with the standard austenitic stainless steel X5CrNi18-8 and with the austenitic twinning-induced plasticity (TWIP) steel X60MnAl17-1. With a total elongation of 45%, the MMn steel showed an increase in yield strength by 300 MPa and in tensile strength by 150 MPa in comparison to both benchmark steels. No deformation twins were observed even after fracture for the MMn steel, which emphasizes the role of the grain size and precipitation-induced change in the austenite stability in controlling the deformation mechanism. The potentio-dynamic polarization measurements in 5% NaCl revealed a very low current density value of 7.2 × 10−4 mA/cm2 compared to that of TWIP steel X60MnAl17-1 of 8.2 × 10−3 mA/cm2, but it was relatively higher than that of stainless steel X5CrNi18-8 of 2.0 × 10−4 mA/cm2. This work demonstrates that the enhanced mechanical properties of the developed MMn steel are tailored by maintaining an ultrafine grain microstructure with a significant amount of nanoprecipitates, while the high corrosion resistance in 5% NaCl solution is attributed to the high Cr and N contents as well as to the ultrafine grain size.

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