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1.
Nanoscale ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38774976

RESUMO

One-dimensional (1D) Zn-based heterostructures have attracted considerable interest in the field of photodetection because of their tunable properties, flexibility, and unique optoelectronic properties. However, designing 1D multi-component Zn-based heterostructures for advanced photodetectors is still a great challenge. Herein, comb-like 1D-1D ZnO-ZnSe heterostructures with ZnO and ZnSe nanowires (NWs) comprising the shaft and teeth of a comb are reported. The length of the ZnO NWs can be modulated in the range of 300-1200 nm. Microstructural characterizations confirm that the 1D heterostructure clearly shows the spatial distribution of individual components. The well-designed structure displays an extended broadband photoresponse and higher photosensitivity than pure ZnSe NWs. Furthermore, ZnSe NWs with an appropriate length of ZnO branches show increased photoresponses of 3835% and 798% compared to those of pure ZnSe NWs under green and red-light irradiation, respectively. In addition, the integrated flexible photodetector presents excellent folding endurance after 1000 bending tests. This well-designed structure has significant potential for other 1D-based semiconductors in optoelectronic applications.

2.
Adv Mater ; 36(7): e2307192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37804146

RESUMO

Low temperature rechargeable batteries are important to life in cold climates, polar/deep-sea expeditions, and space explorations. Here, this work reports 3.5-4 V rechargeable lithium/chlorine (Li/Cl2 ) batteries operating down to -80 °C, employing Li metal negative electrode, a novel carbon dioxide (CO2 ) activated porous carbon (KJCO2 ) as the positive electrode, and a high ionic conductivity (≈5-20 mS cm-1 from -80 °C to room-temperature) electrolyte comprised of aluminum chloride (AlCl3 ), lithium chloride (LiCl), and lithium bis(fluorosulfonyl)imide (LiFSI) in low-melting-point (-104.5 °C) thionyl chloride (SOCl2 ). Between room-temperature and -80 °C, the Li/Cl2 battery delivers up to ≈29 100-4500 mAh g-1 first discharge capacity (based on carbon mass) and a 1200-5000 mAh g-1 reversible capacity over up to 130 charge-discharge cycles. Mass spectrometry and X-ray photoelectron spectroscopy probe Cl2 trapped in the porous carbon upon LiCl electro-oxidation during charging. At -80 °C, Cl2 /SCl2 /S2 Cl2 generated by electro-oxidation in the charging step are trapped in porous KJCO2 carbon, allowing for reversible reduction to afford a high discharge voltage plateau near ≈4 V with up to ≈1000 mAh g-1 capacity for SCl2 /S2 Cl2 reduction and up to ≈4000 mAh g-1 capacity at ≈3.1 V plateau for Cl2 reduction.

3.
Proc Natl Acad Sci U S A ; 120(39): e2310903120, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37729201

RESUMO

Advancing new ideas of rechargeable batteries represents an important path to meeting the ever-increasing energy storage needs. Recently, we showed rechargeable sodium/chlorine (Na/Cl2) (or lithium/chlorine Li/Cl2) batteries that used a Na (or Li) metal negative electrode, a microporous amorphous carbon nanosphere (aCNS) positive electrode, and an electrolyte containing dissolved aluminum chloride and fluoride additives in thionyl chloride [G. Zhu et al., Nature 596, 525-530 (2021) and G. Zhu et al., J. Am. Chem. Soc. 144, 22505-22513 (2022)]. The main battery redox reaction involved conversion between NaCl and Cl2 trapped in the carbon positive electrode, delivering a cyclable capacity of up to 1,200 mAh g-1 (based on positive electrode mass) at a ~3.5 V discharge voltage [G. Zhu et al., Nature 596, 525-530 (2021) and G. Zhu et al., J. Am. Chem. Soc. 144, 22505-22513 (2022)]. Here, we identified by X-ray photoelectron spectroscopy (XPS) that upon charging a Na/Cl2 battery, chlorination of carbon in the positive electrode occurred to form carbon-chlorine (C-Cl) accompanied by molecular Cl2 infiltrating the porous aCNS, consistent with Cl2 probed by mass spectrometry. Synchrotron X-ray diffraction observed the development of graphitic ordering in the initially amorphous aCNS under battery charging when the carbon matrix was oxidized/chlorinated and infiltrated with Cl2. The C-Cl, Cl2 species and graphitic ordering were reversible upon discharge, accompanied by NaCl formation. The results revealed redox conversion between NaCl and Cl2, reversible graphitic ordering/amorphourization of carbon through battery charge/discharge, and probed trapped Cl2 in porous carbon by XPS.

4.
ACS Appl Mater Interfaces ; 15(12): 15279-15289, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36921119

RESUMO

Here, the successful transformation of graphitic carbon with a high degree of graphitization and a nanoflake structure from pyrolytic tire carbon black was demonstrated. First, amorphous carbon black with a porous structure was obtained after pyrolysis and simple preacid treatments. Subsequently, the carbon black was converted into a highly graphitic structure at a relatively low temperature (850 °C) through a facile electrochemical route using molten salt, which is ecofriendly and has high potential for large-scale graphitization compared to conventional incineration techniques. Moreover, we further improved the crystallinity and uniformity of the product simultaneously by directly mixing the metal oxide catalyst Fe2O3 with a carbon precursor. The mechanism of this metal-catalyzed electrochemical graphitization has been discussed in detail. To confirm their potential in practical applications, the as-prepared graphitized nanoflakes were used as conductive additives for silicon anodes in lithium-ion batteries, which showed a performance comparable to those utilizing commercial Super-P additives, exhibiting an initial Coulombic efficiency of approximately 79.7% and a high capacity retention of approximately 45.8% after 100 cycles with a reversible capacity of 1220 mAh g-1 at a current rate of 400 mA g-1. Hence, successfully recovered waste-tire-derived carbon black utilizing a low-temperature Fe2O3-catalyzed electrochemical process opens a pathway in low-temperature graphitization toward a sustainable value-added application in the field of energy storage.

5.
ACS Nano ; 17(1): 84-93, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36575141

RESUMO

In this work, a low-power memristor based on vertically stacked two-dimensional (2D) layered materials, achieved by plasma-assisted vapor reaction, as the switching material, with which the copper and gold metals as electrodes featured by reversible polymorphous phase changes from a conducting 1T-phase to a semiconducting 2H-one once copper cations interacted between vertical lamellar layers and vice versa, was demonstrated. Here, molybdenum diselenide was chosen as the switching material, and the reversible polymorphous phase changes activated by the intercalation of Cu cations were confirmed by pseudo-operando Raman scattering, transmission electron microscopy, and scanning photoelectron microscopy under high and low resistance states, respectively. The switching can be activated at about ±1 V with critical currents less than 10 µA with an on/off ratio approaching 100 after 100 cycles and low power consumption of ∼0.1 microwatt as well as linear weight updates controlled by the amount of intercalation. The work provides alternative feasibility of reversible and all-solid-state metal interactions, which benefits monolithic integrations of 2D materials into operative electronic circuits.

6.
J Am Chem Soc ; 144(49): 22505-22513, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36450002

RESUMO

Developing new types of high-capacity and high-energy density rechargeable batteries is important to future generations of consumer electronics, electric vehicles, and mass energy storage applications. Recently, we reported ∼3.5 V sodium/chlorine (Na/Cl2) and lithium/chlorine (Li/Cl2) batteries with up to 1200 mAh g-1 reversible capacity, using either a Na or a Li metal as the negative electrode, an amorphous carbon nanosphere (aCNS) as the positive electrode, and aluminum chloride (AlCl3) dissolved in thionyl chloride (SOCl2) with fluoride-based additives as the electrolyte [Zhu et al., Nature, 2021, 596 (7873), 525-530]. The high surface area and large pore volume of aCNS in the positive electrode facilitated NaCl or LiCl deposition and trapping of Cl2 for reversible NaCl/Cl2 or LiCl/Cl2 redox reactions and battery discharge/charge cycling. Here, we report an initially low surface area/porosity graphite (DGr) material as the positive electrode in a Li/Cl2 battery, attaining high battery performance after activation in carbon dioxide (CO2) at 1000 °C (DGr_ac) with the first discharge capacity ∼1910 mAh g-1 and a cycling capacity up to 1200 mAh g-1. Ex situ Raman spectroscopy and X-ray diffraction (XRD) revealed the evolution of graphite over battery cycling, including intercalation/deintercalation and exfoliation that generated sufficient pores for hosting LiCl/Cl2 redox. This work opens up widely available, low-cost graphitic materials for high-capacity alkali metal/Cl2 batteries. Lastly, we employed mass spectrometry to probe the Cl2 trapped in the graphitic positive electrode, shedding light into the Li/Cl2 battery operation.

7.
ACS Appl Mater Interfaces ; 14(6): 7814-7825, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35129350

RESUMO

Zinc ion batteries have been extensively studied with an aqueous electrolyte system. However, the batteries suffer from a limited potential window, gas evolution, cathode dissolution, and dendrite formation on the anode. Considering these limitations, we developed an alternative electrolyte system based on deep eutectic solvents (DESs) because of their low cost, high stability, biodegradability, and non-flammability, making them optimal candidates for sustainable batteries. The DES electrolyte enables reversible Zn plating/stripping and effectively suppresses zinc dendrite formation. Furthermore, in-depth characterizations reveal that the energy storage mechanism can be attributed to [ZnCl]+ ion intercalation and the intermediate complex ion plays a pivotal role in electrochemical reactions, which deliver a high reversible capacity of 310 mAh g-1 at 0.1 A g-1and long-term stability (167 mAh g-1 at a current density of 0.3 A g-1 after 300 cycles, Coulombic efficiency: ∼98%). Overall, this work represents our new finding in rechargeable batteries with the DES electrolyte.

8.
Small ; 18(5): e2104168, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34821034

RESUMO

A multifunctional ion-sensitive floating gate Fin field-effect transistor (ISFGFinFET) for hydrogen and sodium detection is demonstrated. The ISFGFinFET comprises a FGFET and a sensing film, both of which are used to detect and improve sensitivity. The sensitivity of the ISFGFinFET can be adjusted by modulating the coupling effect of the FG. A nanoseaweed structure is fabricated via glancing angle deposition (GLAD) technology to obtain a large sensing area to enhance the sensitivity for hydrogen ion detection. A sensitivity of 266 mV per pH can be obtained using a surface area of 3.28 mm2 . In terms of sodium ion detection, a calix[4]arene sensing film to monitor sodium ions, obtaining a Na+ sensitivity of 432.7 mV per pNa, is used. In addition, the ISFGFinFET demonstrates the functionality of multiple ions detection simultaneously. The sensor arrays composed of 3 × 3 pixels are demonstrated, each of which comprise of an FGFET sensor and a transistor. Furthermore, 16 × 16 arrays with a decoder and other peripheral circuits are constructed and simulated. The performance of the proposed ISFGFinFET is competitive with that of other state-of-the-art ion sensors.


Assuntos
Técnicas Biossensoriais , Transistores Eletrônicos , Técnicas Biossensoriais/métodos , Íons , Tecnologia
9.
Nanoscale ; 13(44): 18626-18631, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34734625

RESUMO

Silicon (Si) anode materials have attracted substantial interest due to their high theoretical capacity. Here, the growth of helical Si@Cu3Si nanorod arrays via glancing angle deposition (GLAD) followed by an annealing process is reported. Pre-deposited Cu atoms were driven into Si-nanorods and successfully reacted with Si to form a Si-Cu alloy at a high temperature. By varying the rotation rate and annealing temperature, the resultant Si@Cu3Si nanorod arrays showed a reasonably accessible surface area with precise control spacing behavior in favor of accommodating Si volume expansion. Meanwhile, the Si@Cu3Si anode materials showed higher electrical conductivity, facilitating Li+ ion diffusion and electron transfer. The Si@Cu3Si nanorod arrays in half cells exhibited a volumetric capacity as high as 3350.1 mA h cm-3 at a rate of 0.25 C and could maintain 1706.7 mA h cm-3 after 100 cycles, which are superior to those of pristine Si materials. This facile and innovative technology provided new insights into the development of Si-based electrode materials.

10.
ACS Nano ; 14(10): 12668-12678, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-32813498

RESUMO

Transition metal dichalcogenides (TMDCs) have recently attracted a tremendous amount of attention owing to their superior optical and electrical properties as well as the interesting and various nanostructures that are created by different synthesis processes. However, the atomic thickness of TMDCs limits the light absorption and results in the weak performance of optoelectronic devices, such as photodetectors. Here, we demonstrate the approach to increase the surface area of TMDCs by a one-step synthesis process of TMDC nanowalls from WOx into three-dimensional (3D) WS2 nanowalls. By utilizing a rapid heating and rapid cooling process, the formation of 3D nanowalls with a height of approximately 150 nm standing perpendicularly on top of the substrate can be achieved. The combination of core-shell colloidal quantum dots (QDs) with three different emission wavelengths and 3D WS2 nanowalls further improves the performance of WS2-based photodetector devices, including a photocurrent enhancement of 320-470% and shorter response time. The significant results of the core-shell QD-WS2 hybrid devices can be contributed by the high nonradiative energy transfer efficiency between core-shell QDs and the nanostructured material, which is caused by the spectral overlap between the emission of core-shell QDs and the absorption of WS2. Besides, outstanding NO2 gas-sensing performance of core-shell QDs/WS2 devices can be achieved with an extremely low detection limit of 50 ppb and a fast response time of 26.8 s because of local p-n junctions generated by p-type 3D WS2 nanowalls and n-type core-shell CdSe-ZnS QDs. Our work successfully reveals the energy transfer phenomenon in core-shell QD-WS2 hybrid devices and shows great potential in commercial multifunctional sensing applications.

11.
ACS Nano ; 14(7): 8539-8550, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32520534

RESUMO

The rechargeable aluminum-ion battery (AIB) is a promising candidate for next-generation high-performance batteries, but its cathode materials require more development to improve their capacity and cycling life. We have demonstrated the growth of MoSe2 three-dimensional helical nanorod arrays on a polyimide substrate by the deposition of Mo helical nanorod arrays followed by a low-temperature plasma-assisted selenization process to form novel cathodes for AIBs. The binder-free 3D MoSe2-based AIB shows a high specific capacity of 753 mAh g-1 at a current density of 0.3 A g-1 and can maintain a high specific capacity of 138 mAh g-1 at a current density of 5 A g-1 with 10 000 cycles. Ex situ Raman, XPS, and TEM characterization results of the electrodes under different states confirm the reversible alloying conversion and intercalation hybrid mechanism during the discharge and charge cycles. All possible chemical reactions were proposed by the electrochemical curves and characterization. Further exploratory works on interdigital flexible AIBs and stretchable AIBs were demonstrated, exhibiting a steady output capacity under different bending and stretching states. This method provides a controllable strategy for selenide nanostructure-based AIBs for use in future applications of energy-storage devices in flexible and wearable electronics.

12.
Small ; 16(24): e2000020, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32419389

RESUMO

Transparent flexible energy storage devices are considered as important chains in the next-generation, which are able to store and supply energy for electronic devices. Here, aluminum-doped zinc oxide (AZO) nanorods (NRs) and nickel oxide (NiO)-coated AZO NRs on muscovites are fabricated by a radio frequency (RF) magnetron sputtering deposition method. Interestingly, AZO NRs and AZO/NiO NRs are excellent electrodes for energy storage application with high optical transparency, high conductivity, large surface area, stability under compressive and tensile strain down to a bending radius of 5 mm with 1000 bending cycles. The obtained symmetric solid-state supercapacitors based on these electrodes exhibit good performance with a large areal specific capacitance of 3.4 mF cm-2 , long cycle life 1000 times, robust mechanical properties, and high chemical stability. Furthermore, an AZO/NiO//Zn battery based on these electrodes is demonstrated, yielding a discharge capacity of 195 mAh g-1 at a current rate of 8 A g-1 and a discharge capacity of over 1000 cycles with coulombic efficiency to 92%. These results deliver a concept of opening a new opportunity for future applications in transparent flexible energy storage.

13.
ACS Appl Mater Interfaces ; 12(24): 27064-27073, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32364367

RESUMO

Aluminum-sulfur batteries (ASBs) have attracted substantial interest due to their high theoretical specific energy density, low cost, and environmental friendliness, while the traditional sulfur cathode and ionic liquid have very fast capacity decay, limiting cycling performance because of the sluggishly electrochemical reaction and side reactions with the electrolyte. Herein, we demonstrate, for the first time, excellent rechargeable aluminum-selenium batteries (ASeBs) using a new deep eutectic solvent, thiourea-AlCl3, as an electrolyte and Se nanowires grown directly on a flexible carbon cloth substrate (Se NWs@CC) by a low-temperature selenization process as a cathode. Selenium (Se) is a chemical analogue of sulfur with higher electronic conductivity and lower ionization potential that can improve the battery kinetics on the sluggishly electrochemical reaction and the reduction of the polarization where the thiourea-AlCl3 electrolyte can stabilize the side reaction during the reversible conversion reaction of Al-Se alloying processes during the charge-discharge process, yielding a high specific capacity of 260 mAh g-1 at 50 mA g-1 and a long cycling life of 100 times with a high Coulombic efficiency of nearly 93% at 100 mA g-1. The working mechanism based on the reversible conversion reaction of the Al-Se alloying processes, confirmed by the ex situ Raman, XRD, and XPS measurements, was proposed. This work provides new insights into the development of rechargeable aluminum-chalcogenide (S, Se, and Te) batteries.

14.
Phys Ther Sport ; 40: 99-106, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31514108

RESUMO

OBJECTIVE: Round shoulder posture (RSP) may exaggerate symptoms of subacromial impingement. The effects of kinesiology taping with exercise on posture, pain, and functional performance were investigated in subjects with impingement and RSP. DESIGN: This study was a single-blinded randomized controlled trial. SETTING: An outpatient rehabilitation clinic in a university hospital. PARTICIPANTS: Thirty-four subjects with subacromial impingement and RSP. INTERVENTIONS: Kinesiology taping with and without tension was applied 2 times per week for 4 weeks. Both groups also performed strengthening and stretching exercises 3 times per week for 4 weeks. MAIN OUTCOME MEASUREMENTS: The pain level, shoulder angle and self-reported score were evaluated at pre-intervention, 2-week post-intervention and 4-week post-intervention time points. RESULTS: Functional performance improved after intervention in both groups (p = 0.027). A greater decrease in pain level was related to better functional performance of the shoulder in both groups (r = -0.760 and -0.674; p < 0.010). Moderate correlations were found for posture and functional performance of the shoulder in the intervention group (0.48). CONCLUSION: Four weeks of strengthening and stretching exercises with or without kinesiology taping improved functional performance in subjects with impingement and RSP. Improvement in clinical symptoms was related to better performance of posture.


Assuntos
Fita Atlética , Terapia por Exercício , Síndrome de Colisão do Ombro/terapia , Ombro/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Postura , Síndrome de Colisão do Ombro/fisiopatologia , Dor de Ombro/fisiopatologia
15.
Nanoscale Res Lett ; 14(1): 213, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31240467

RESUMO

In this work, three-dimensional (3D) CoMoSe4 nanosheet arrays on network fibers of a carbon cloth denoted as CoMoSe4@C converted directly from CoMoO4 nanosheet arrays prepared by a hydrothermal process followed by the plasma-assisted selenization at a low temperature of 450 °C as an anode for sodium-ion battery (SIB) were demonstrated for the first time. With the plasma-assisted treatment on the selenization process, oxygen (O) atoms can be replaced by selenium (Se) atoms without the degradation on morphology at a low selenization temperature of 450 °C. Owing to the high specific surface area from the well-defined 3D structure, high electron conductivity, and bi-metal electrochemical activity, the superior performance with a large sodium-ion storage of 475 mA h g-1 under 0.5-3 V potential range at 0.1 A g-1 was accomplished by using this CoMoSe4@C as the electrode. Additionally, the capacity retention was well maintained over 80 % from the second cycle, exhibiting a satisfied capacity of 301 mA h g-1 even after 50 cycles. The work delivered a new approach to prepare a binary transition metallic selenide and definitely enriches the possibilities for promising anode materials in SIBs with high performances.

16.
Microbiol Immunol ; 54(8): 452-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20646209

RESUMO

Escherichia coli OmpT, located in the outer membrane, has been characterized as a plasminogen activator, with the ability to hydrolyze protamine and block its entry. In this investigation, a complex of low molecular weight cationic peptides purified from human urine by a combination of membrane ultrafiltration and weak cation exchange chromatography was characterized. The impact of OmpT on E. coli resistance to urinary cationic peptides was investigated by testing ompT knockout strains. The ompT mutants were more susceptible to urinary cationic peptides than ompT(+) strains, and this difference was abolished by complementation of the mutants with pUC19 carrying the ompT gene. The urinary protease inhibitor ulinastatin greatly decreased the resistance of the ompT(+) strains. Overall, the data indicate that OmpT may help E. coli persist longer in the urinary tract by enabling it to resist the antimicrobial activity of urinary cationic peptides.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Farmacorresistência Bacteriana , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/farmacologia , Urina/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/urina , Proteínas da Membrana Bacteriana Externa/antagonistas & inibidores , Proteínas da Membrana Bacteriana Externa/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/urina , Proteínas de Escherichia coli/antagonistas & inibidores , Proteínas de Escherichia coli/genética , Humanos , Masculino , Peptídeo Hidrolases/genética , Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/urina
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