Times Longer Lifetime Research Articles

Eye Tear Activated Mg‐Air Battery Driven by Natural Eye Blinking for Smart Contact Lenses

AbstractA sliding electrolyte metal‐air microbattery driven by natural eye blinking motion is demonstrated as a source of electrical energy that can be integrated with smart contact lens platforms. The metal‐air battery (footprint 10 mm2) consists of a Mg anode and a Pt cathode, patterned on an insulating substrate and the battery electrolyte is a film of eye‐tear fluid that is periodically dragged on top of the electrodes during the natural eye‐blinking cycle, which activates the battery. When tested with an eye emulator, the open‐circuit voltage across the eye‐tear activated metal‐air battery (ETMAB) is 2.2 V. Impedance matching analysis reveals a maximum battery‐specific capacity of 3561 mAh g–1 obtained at a discharge current density of 5 mA cm–2. The blinking activated battery exhibits the maximum generated power density of 1.3 mW cm–2 at the load of 740 Ω. The blinking ETMAB delivers eight times higher energy output and more than three times longer lifetime than achievable with static ETMAB designs.

Photodissociation Dynamics of Nitric Oxide from N-Acetylcysteine- or N-Acetylpenicillamine-bound Roussin's Red Ester.

The photochemical release of nitric oxide (NO) from a NO precursor is advantageous in terms of spatial, temporal, and dosage control of NO delivery to target sites. To realize full control of the quantitative NO administration from photoactivated NO precursors, it is necessary to have detailed dynamical information on the photodissociation of NO from NO precursors. We synthesized two new water-soluble Roussin’s red esters (RREs), [Fe2(μ-N-acetylcysteine)2(NO)4] and [Fe2(μ-N-acetylpenicillamine)2(NO)4], which have five times longer lifetime than the well-known [Fe2(μ-cysteine)2(NO)4]. The photodissociation dynamics of NO from these RREs in water were investigated over a broad time range from 0.3 ps to 10 μs after excitation at 310 and 400 nm using femtosecond time-resolved infrared (IR) spectroscopy. When these RREs are excited, they either release one NO, producing a radical species deficient in one NO (R), [Fe2(μ-RS)2(NO)3], or relax into the ground state without photodeligation via an electronically excited intermediate state (M). R appears immediately after photoexcitation, suggesting that one NO is photodissociated faster than 0.3 ps. A certain fraction of R undergoes geminate recombination (GR) with NO with a time constant of 7–9 ps, while the remaining R competitively binds to the solvent. Solvent-bound R eventually bimolecularly recombines with NO with a rate constant of (1.3–1.6) × 108 M–1 s–1. For a given RRE molecule, the fractional yield of M (0.62–0.76) depends on the excitation wavelength (λex); however, the relaxation time of M (6 ± 1 ns) is independent of λex. Although the primary quantum yield of NO photodissociation (Φ1) was found to be 0.24–0.38, the final yield of NO suitable for other reactions (Φ2) was reduced to 0.14–0.29 due to the picosecond GR of the dissociated NO with R. Detailed photoexcitation dynamics of RRE can be utilized in the quantitative control of NO administration at a specific site and time, promoting pin-point usage of NO in chemistry and biology. We demonstrate that femtosecond IR spectroscopy combined with quantum chemical calculations is a powerful method for obtaining detailed dynamic information on photoactivated NO precursors such as Φ1 and Φ2, the GR yield, and secondary reactions of the nascent photoproducts, which are essential information for the design of efficient photoactivated NO precursors and their quantitative utilization.

11,11-Dimethyl-11H-indeno[1,2-b]indolo[1,2,3-jk]carbazole: A rigid chromophore with novel amalgamation strategy for long lifetime blue fluorescent organic light-emitting diodes

In this work, we report a novel chromophore, 11,11-dimethyl-11H-indeno[1,2-b]indolo[1,2,3-jk]carbazole (IDFL), developed from a indenocarbazole building block and a blue fluorescent emitter, 11,11-dimethyl-N2,N2,N8,N8-tetraphenyl-11H-indeno[1,2-b]indolo[1,2,3-lm]carbazole-2,8-diamine (IDFL-2DPA), derived from the IDFL by diphenylamine functionalization. The device fabricated using the IDFL-2DPA emitter offered blue emission with a very small full-width at half maximum of 32 nm in addition to high external quantum efficiency above 5% and 4 times longer lifetime than that of pyrene-based blue device. Therefore, the IDFL-2DPA emitter was appropriate as the pure blue emitter with high color purity, high efficiency, and long device lifetime.

Antimony Doped Tin Oxide Nanoparticles Deposited onto Nb−TiO2 Nanotubes for Electrochemical Degradation of Bio‐refractory Pollutions

AbstractTo improve the service life of SnO2−Sb electrodes in degradation of refractory wastewater, we report anodic information of tin oxide antimony on top of Nb−TiO2 nanotubes (Nb−Ti/Nb−TiO2−NTs/ATONPs) prepared through screen‐printing. It was found that the Nb−Ti/Nb−TiO2−NTs/ATONPs anodes presented a significantly enhanced in electro‐catalytic oxidation performance (in Acid Red 73) compared to titanium‐based tin antimony electrodes (Ti/ATONPs). Additionally, the electrochemical properties and the stability were further studied by the electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), cyclic voltammetry (CV), chronoamperometry (CA) measurements and accelerated life test, respectively. These results indicated that Nb−TiO2−NTs/ATONPs anode possessed Nb−TiO2 nanotubes which exhibited a higher oxygen evolution potential (2.24 V vs. Ag/AgCl), as well as a better wettability, a larger current at constant potential and 2.1 times longer lifetime than the conventional Ti/ATONPs anode.

5‐2: Fluorescent OLED Achieving External Quantum Efficiency over 20% and Longer Lifetime than Phosphorescent OLED

This paper reports an exciton‐harvesting fluorescent OLED achieving an external quantum efficiency of 22% and three times longer lifetime than a phosphorescent OLED in the same emission color. A fluorescent dopant designed to prevent Dexter energy transfer from an energy donor plays an important role in such high performance.

Enhanced gas barrier property of stacking-controlled reduced graphene oxide films for encapsulation of polymer solar cells

Compact stacking of building blocks is essential in order to utilize the impermeable nature of reduced graphene oxide (rGO) for encapsulating barriers in organic electronics. To obtain the desired accumulation characteristic, rGO films were fabricated via spraying process using phase-controlled graphene oxide (GO) dispersion. The rGO laminate prepared from the isotropic-phase dispersion exhibits a more favorable face-on orientation of rGO building blocks than that from the nematic-phase GO, which implies effective stacking of building blocks. As a result, the resulting gas barrier performance of the low-temperature-annealed rGO film is superior to previously reported low-temperature solution-processed materials. Fabricated gas barriers are adopted to seal the polymer solar cell with 57.2 times longer lifetime than that of the unsealed device. A device covered by an optimized rGO/polyethylene naphthalate gas barrier maintains photovoltaic performance as high as 88% of the initial efficiency after 28 days.

Quantum error correction and universal gate set operation on a binomial bosonic logical qubit

Logical qubit encoding and quantum error correction (QEC) have been experimentally demonstrated in various physical systems with multiple physical qubits, however, logical operations are challenging due to the necessary nonlocal operations. Alternatively, logical qubits with bosonic-mode-encoding are of particular interest because their QEC protection is hardware efficient, but gate operations on QEC protected logical qubits remain elusive. Here, we experimentally demonstrate full control on a single logical qubit with a binomial bosonic code, including encoding, decoding, repetitive QEC, and high-fidelity (97.0% process fidelity on average) universal quantum gate set on the logical qubit. The protected logical qubit has shown 2.8 times longer lifetime than the uncorrected one. A Ramsey experiment on a protected logical qubit is demonstrated for the first time with two times longer coherence than the unprotected one. Our experiment represents an important step towards fault-tolerant quantum computation based on bosonic encoding.

Lifetime extension in green thermally activated delayed fluorescent organic light-emitting diodes by increasing excited state bond dissociation energy

A lifetime extending molecular design approach by increasing the bond dissociation energy of the thermally activated delayed fluorescent (TADF) emitters was investigated. A TADF emitter with a molecular design having the donors in a planar manner, 4-(9H-carbazol-9-yl)-6-(9,9″-diphenyl-9H,9′H,9″H-[3,3′:6′,3″-tercarbazol]-9′-yl)isophthalonitrile (TCzIPN), was compared with state of the art green TADF emitter. The two emitters were green TADF emitters with similar peak wavelengths, but the TCzIPN exhibited three times longer lifetime than the current TADF emitter. Analysis of bond dissociation energy of the TADF emitters revealed that the weak CN bond of the TCzIPN was stabilized by small dihedral angle between donor and an aromatic linker. This was confirmed by exciton stability test of the emitters, and the CN bond stabilization effect in triplet excited state was well correlated with the lifetime improvement of the TCzIPN devices.

20‐3: Novel Host‐Guest System for Drastic Improvement in the Lifetime of a Deep‐Red OLED that Satisfies the Red Chromaticity of the BT.2020 Standard

We developed a novel host‐guest system that increases the lifetime of a deep‐red phosphorescent OLED covering the wide color gamut of the BT.2020 standard. An OLED that employs this host‐guest system has a ~5.4 times longer lifetime than an OLED that employs the conventional system.

Sintering induced the failure behavior of dense vertically crack and lamellar structured TBCs with equivalent thermal insulation performance

Abstract Both thermal cyclic lifetime and thermal barrier performance are essentially important to the application of thermal barrier coatings (TBCs). In this study, equivalent thermal insulation conception is introduced to the design of TBCs to fairly compare different structured TBCs. Dense vertically crack (DVC) structured TBCs and the lamellar structured TBCs with same top coat thickness of 1000 µm (D1000 and L1000), and lamellar structured TBCs with 570 µm (L570, equivalent thermal insulation performance with D1000) top coat were prepared. Their lifetimes were evaluated under gradient thermal cyclic test. D1000 TBC shows a rather longer lifetime than L1000 TBC because of the alleviation of vertically cracks, but D1000 TBC possesses a much lower thermal barrier performance than L1000 TBC due to the dense structure of D1000 TBC. However, for the TBCs with the same equivalent thermal insulation performance, L570 TBC presents a more than two times longer lifetime than D1000 TBC. TGO thickening and phase transformation were proved not responsible for the failure of L1000 and D1000 TBCs in the present condition. The in-plane elastic modulus and Vickers hardness across top coat thickness were examined, and the results proved that the mechanical evolution of the top coat after high temperature exposure resulting in the competition between driving force and cracking resistance dominates the failure behavior of TBCs. This study is beneficial for the comprehensively understanding of the failure behavior of DVC and lamellar structured TBCs, and thereby shed light to further coating structure optimization and design innovation.

Using an organic radical precursor as an electron injection material for efficient and stable organic light-emitting diodes

Materials with strong reducibility have been used as electron injection layers (EILs) to lower the work function of cathodes and reduce the driving voltage of organic light-emitting diodes (OLEDs). However, the most prominent electron injection materials presented so far are high-temperature-evaporable inorganic salts based on alkaline metals, which suffer from a high tendency of metal diffusion throughout the organic layer and thus reduce the device efficiency and stability. Here, we introduce a new kind of EIL based on a stable precursor of a strongly reducing organic radical. By using an organic precursor, we are able to take the advantage of the low-evaporation-temperature and avoid the problem of metal diffusion, thus improving the device efficiency and stability. Ultraviolet photoelectron spectroscopy (UPS) study indicates that inserting a thin layer of organic radical between the electron transport layer and cathode could greatly reduce the electron injection barrier due to the strong interaction of radical with cathode and the electron transporting material. As a result, OLEDs with an organic radical as the EIL showed a 25.2% higher efficiency and 2.2 times longer lifetime than the control device with conventional LiF as the EIL.

Synthesis and Electroluminescence of Novel Pyrene-Fused Chromophores.

Using 4,9-dibromopyrene as a key intermediate, two new fused-core compounds, TP-PFF and TP-PFC-TP, were synthesized. These compounds not only exhibited excellent thermal stability but also yielded superior electroluminescence (EL) devices with a lower turn-on voltage, over 50% greater efficiency, and over 3 times longer lifetime than did a similar compound lacking a fused core. This new core-forming method can be applied in various applications with many different core groups.

Stable blue thermally activated delayed fluorescent organic light-emitting diodes with three times longer lifetime than phosphorescent organic light-emitting diodes.

High quantum efficiency above 18% and extended lifetime three times longer than that of phosphorescent organic light-emitting diodes (OLEDs) are demonstrated in blue thermally activated delayed fluorescent OLEDs.

Graphene stripper foils

Thin carbon and metal foils have been used in heavy ion accelerators for charge stripping. The power dissipated by a particle beam in a foil can be as high as 3 kW or greater, which results in short lifetimes of conventional stripper foils. Graphene stripper foils can overcome critical limitations of other materials due to a unique combination of their exceptional physical properties. The authors have fabricated graphene foils with diameters up to 13 cm and area densities of 0.1 to 3.0 mg/cm2 by reduction of graphene oxide in an aqueous dispersion followed by pressure filtration. The foils were characterized by a number of analytical techniques, including scanning electron microscopy, thermogravimetric analysis, and x-ray photoelectron spectroscopy, and proved their superior mechanical and thermal properties. Preliminary ion beam tests showed that the graphene stripper foils possess up to four times longer lifetime, as opposed to conventional carbon foils.

Multilayer carbon foils for cyclotron beam extraction

The TRIUMF Applied Technology Group operates high-power industrial cyclotrons for commercial radioisotope production. Two of these cyclotrons, TR30-1 and TR30-2, are capable of accelerating H − ions to an energy of 30 MeV and beam currents in excess of 1000 μA. For many years, amorphous carbon foils of approximately 2.0 μm thickness have been utilized to extract proton beams from these accelerators. Novel multilayer foils consisting of layers of amorphous and diamond-like carbon (DLC) of 2.0±0.2 μm thickness were manufactured in-house by carbon arc and pulsed laser deposition, respectively. In the TR30 cyclotrons, the new composite foils with 25% DLC content show a three times longer lifetime than the purely amorphous foils, while maintaining their excellent physical and mechanical characteristics during irradiation.

Dramatic improvement of catalyst life by rhodium and cerium additives for Ni-based reforming catalysts

Rhodium and cerium were found to be suitable additives for improving the sulfur-tolerance of Ni-based gasoline reforming catalysts. In these cases, the Rh content was only 0.1 wt.% with 5 wt.% of Ce. The lifetime of Rh-Ce-modified Ni-based catalyst is found to be above 600 hours at 1023K, which is over a ten times longer lifetime than that of the unmodified catalysts, when premium gasoline was used.

White organic light-emitting devices with mixed interfaces between light emitting layers

White organic light-emitting devices with mixed interfaces between emitting layers (MI-EML WOLEDs) showed luminance and efficiency as large as 26213cd∕m2 and 9.85cd∕A. Efficiencies of MI-EML WOLEDs were about 1.5 times better than those of conventional three-EML WOLEDs for luminance of 1000–5000cd∕m2, and their half-decay lifetime showed 3.1 times improvement. Note that if the authors operate typical active-matrix mobile-phone displays based on combination of WOLED and color filters to produce standard white emission for high definition televisions and illumination sources, MI-EML WOLEDs will have advantages of 25% less power consumption and 2.8 times longer lifetime over conventional three-EML WOLEDs.

Cu surface treatment influence on Si adsorption properties of CuSiN self-aligned barriers for sub-65 nm technology node

Self-aligned barriers are widely investigated either in replacement of dielectric liners to decrease the total interconnect k value or as a treatment prior standard dielectric barrier deposition to improve reliability performances. In this paper, a technique based on the modification of the Cu surface is proposed. It consists first in removing native Cu oxide, then, enriching Cu surface with Si atoms followed by a nitridation step to complete the so called CuSiN self-aligned barrier. The dependency of Cu surface silicidation on Cu crystallographic orientation is described, evidencing two silicidation mechanisms: Si interstitial incorporation into Cu and Cu atoms substitution by Si atoms. He diluted in H 2 cleaning plasma prior to silicidation is demonstrated both to decrease Cu grain surface ability to silicidation compared H 2 plasma and to limit Si incorporation into Cu at grain boundaries. Compared to a standard SiCN barrier, CuSiN self-aligned barriers integrated as a treatment prior to SiCN evidenced at least four times longer lifetime under electromigration tests.

Epitaxial Aluminum Electrodes on Theta Rotated Y-X LiTaO3 Piezoelectric Substrate for High Power Durable SAW Duplexers.

ABSTRACTHigh power durable electrodes have been successfully grown on 38.5° rotated Y-X LiTaO3 piezoelectric substrates featuring epitaxial Al films with a pseudo-homoepitaxial Ti intermediate layer. We found that a two-step process sequence in the deposition temperature of an intermediate layer could make it possible for an Al/Ti structure to grow epitaxially on low-cut-angle Y-X LiTaO3. Specified epitaxial relationship was Al(111)<011>//Ti(001)<100>//LiTaO3(001)<100>. Duplexers with epitaxial Al electrodes had a breakdown power above 6 W and more than ten times longer lifetime in contrast to filters with polycrystalline electrodes of which the breakdown power is 3.4 W. Epitaxial electrodes with extremely less grain boundary can improve power durability because self-diffusion of Al atoms occurs mainly in the grain boundary of the film. Material variation of epitaxial electrodes will be discussed as well.

Signal strength-based link stability estimation in ad hoc wireless networks

An enhanced link stability estimation model for ad hoc wireless networks is presented. In the comparison of three models, the routing with the proposed model finds a route that has the longest lifetime with little increase in hop-length. Especially, the route has two times longer lifetime than the shortest path route.