We proposed the use of Copper (Cu) and Zinc (Zn) nanoparticles as the electrodes for thin-film microbatteries in the applications of micro-scale sensors. Compared to the widely used lithium-based batteries, Cu and Zn ...
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ISBN:
(纸本)9781627482431
We proposed the use of Copper (Cu) and Zinc (Zn) nanoparticles as the electrodes for thin-film microbatteries in the applications of micro-scale sensors. Compared to the widely used lithium-based batteries, Cu and Zn nanoparticles are less expensive, less prone to oxidation (thus involving simpler fabrication steps) and flammability, safe to use, and only requires very simple fabrication processes. Even though the voltage output is inherently smaller (∼1V) than conventional lithium-based batteries, it is sufficient for low-voltage Integrated Circuits (IC) technologies such as 130 nm and 90 nm channel length transistor processes. Commercial paper will be used as the separator to demonstrate the battery capacity. Paper that acts as the separator is slurry-casted with nanoparticles (30-40 nm in size) on both sides. The thickness of the metal nanoparticles-coated thin films and the paper separator are 1 μm and 100 μm, respectively. The electrodes were developed to achieve high conductivity (lower than 1 (Ω·cm)-1) with smooth surface, good adhesion, and flexibility. The metal nanoparticles will be formulated to slurry solutions for screen printing or ink-jet printing for the battery fabrication. For fabrication purposes, the slurries viscosity is approximately in the range of 10-12 cPs at the operating temperature, a surface tension between 28-33 dynes/cm. During the fabrication process including printing/coating and sintering, reductive environment is required to minimize the oxidation. AFM (Atomic Force Microscopy) and EDS (Energy Dispersive Spectroscopy) results will be employed to demonstrate the surface morphology as well as the percentages of metal oxides. Batteries will be tested with and without an ionic liquid for comparison. Humidity effects on the battery performance will also be discussed. Different geometries that are designed to make the batteries with higher voltage or charge will be proposed. Characterization results will include the open-circuit voltage,
The development of novel high-performance cathodes is essential to reduce Solid Oxide Fuel Cell (SOFCs) operation to low and intermediate temperatures. To that end, the performance of CeO 2 -based composite cathodes i...
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The development of novel high-performance cathodes is essential to reduce Solid Oxide Fuel Cell (SOFCs) operation to low and intermediate temperatures. To that end, the performance of CeO 2 -based composite cathodes is very attractive. In the present work, LSM (La0.8 Sr0.2 MnO3 ), LSCF (La0.5Sr0.5Co0.8Fe0.2O3 ) and SDC (Ce0.8Sm0.2O1.9 ) powders were synthesized by different synthesis methods and used to prepare SOFC composite film cathodes. LSM-SDC and LSCF-SDC composite powders were obtained by milling. Composite films were deposited onto yttria stabilized zirconia (YSZ) electrolytes and characterized by scanning electron microscopy. Preliminary performance tests were carried out using a single cell having a LSCF-SDC cathode. I-V curves indicated that the cell had qualitatively good performance with maximum power density of 19 mW/cm 2 at 800℃. The preparation of LSM and LSCF composites by mixing SDC, synthesized by the method proposed herein is an innovative alternative for the production of high performance ceramic materials for SOFC cathodes.
We demonstrate the strong dependency of the isotropic-nematic (I-N) transition of discotic suspensions on the aspect ratio (ξ = thickness/diameter) via control of the sizes of pristine ZrP crystals and subsequent exf...
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We demonstrate the strong dependency of the isotropic-nematic (I-N) transition of discotic suspensions on the aspect ratio (ξ = thickness/diameter) via control of the sizes of pristine ZrP crystals and subsequent exfoliation to monolayers. The size fractionation of the I-N transition facilitates the analysis of the effect of polydispersity. A systematic variation in the aspect ratio in the low aspect ratio region (0.001 < ξ < 0.01) showed that the I-N transition volume fraction increases with the aspect ratio in agreement with computer simulations. It was found that the transition volume fractions scale with aspect ratio φI,N = mξ1.36±0.07, where the prefactor m strongly depends on size polydispersity for φN but does not depend on size polydispersity for φI with φI and φN being the volume fractions of the isotropic and the nematic phases on the cloud curves, respectively.
In this paper, we explore the effects of misfit strain fields on both heterogeneous nucleation behavior and anisotropic growth of islands at submonolayer coverages and compositional patterning at complete monolayer co...
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In this paper, we explore the effects of misfit strain fields on both heterogeneous nucleation behavior and anisotropic growth of islands at submonolayer coverages and compositional patterning at complete monolayer coverage via simulations of a phase-field crystal model. In particular, deposition on top of a herringbone structure and quasicrystalline (QC) substrate are considered, the former representing a system with spatially periodic misfit strain fields arising from the presence of surface dislocations, and the latter representing a system which inherently possesses a wide range of local, aperiodic misfit patterns. In the case of single-component systems, we demonstrate that misfit strain fields lead to heterogeneous nucleation behavior and anisotropic island growth. In the case of QC substrate, a wide range of morphologies, such as coexistence of locally hexagonally ordered atomic clusters within a larger scale arrangement with overall QC symmetry and so-called “starfish” aggregates, is observed in a pure system at submonolayer coverages when the adlayer-substrate interaction strength and lattice mismatch are tuned. In the case of bulk-immiscible binary systems at complete monolayer coverage, strain-stabilized compositional domains emerge at low line tension values for both substrates. Interestingly, the compositional domains on the QC substrate inherit their symmetries at sufficiently low line tension values, while at larger line tension values, the domain structure begins to resemble the classical spinodal microstructure. Such domain structures should be readily observable in colloidal systems in which attractive interparticle and particle-substrate interactions can be tuned.
A new prototype of Uric Acid (UA) biosensor is constructed by combining high electron mobility transistors (HEMTs) with Zinc Oxide Nanotetrapods (T-ZnOs). T-ZnOs are synthesized by chemical vapor deposition (CVD). The...
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A new prototype of Uric Acid (UA) biosensor is constructed by combining high electron mobility transistors (HEMTs) with Zinc Oxide Nanotetrapods (T-ZnOs). T-ZnOs are synthesized by chemical vapor deposition (CVD). These T-ZnOs with high specific areas are evenly distributed on the gate areas of HEMTs to improve the sensitivity of the HEMTs. Uricase is then immobilized on the T-ZnOs by their different isoelectric points (IEP). When different UA solutions are added to the gate areas of HEMTs, the biosensors respond in around one second through signal current change. The fabricated biosensors can detect target UA in solutions of concentrations ranging from 0.2 nM to 0.2 mM with a detection limit of 0.2 nM.
Bond integrity is of interest to researchers in non-destructive evaluation because it is used as an indicator when assessing the health of structures. In this study, a plate waveguide on a half space is examined to fi...
Bond integrity is of interest to researchers in non-destructive evaluation because it is used as an indicator when assessing the health of structures. In this study, a plate waveguide on a half space is examined to find features associated with bond integrity. Analytical and finite element models are developed to describe wave propagation. Mode and frequency selection optimization is discussed. Preliminary results suggest that changes in arrival time and amplitude can be used to detect the length of a very weak bond when using a special mode of strong in-plane displacement at the interface.
Biodegradation of synthetic and natural materials by various microorganisms affects a wide range of industrial processes and techniques. One of the modern ways to protect of the synthetic and natural materials from th...
Biodegradation of synthetic and natural materials by various microorganisms affects a wide range of industrial processes and techniques. One of the modern ways to protect of the synthetic and natural materials from the action of aggressive microorganisms is a creation of novel antibiocorrosive covers with high bioactivity and multivectorial and directional action based on inorganic-organic hybrid composites [1, 2].
A significant level of cold cracking has been observed within direct chill (DC) cast, high-strength magnesium alloy Elektron WE43. These cracks have been attributed to the formation of significant residual stresses du...
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