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1.
J Phys Chem Lett ; 15(17): 4669-4678, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38651977

RESUMO

The Zn dendrite and hydrogen evolution reaction have been a "stubborn illness" for the life span of zinc anodes, which significantly hinders the development of aqueous zinc batteries (AZBs). Herein, considering the ingenious molecular structure, a multifunctional additive based on the synergistic regulation of cations and anions at the interface is designed to promote a dendrite-free and stable Zn anode. Theoretical calculations and characterization results verified that the electrostatic shield effect of the cation, the solvation sheath structure, and the bilayer structural solid electrolyte film (SEI) jointly account for the uniform Zn deposition and side reaction suppression. Ultimately, a remarkably high average Coulombic efficiency (CE) of 99.4% is achieved in the Zn||Cu cell for 300 cycles, and a steady charge/discharge cycling over 3000 and 300 h at 1.0 mA cm-2/1.0 mAh cm-2 and 10 mA cm-2/10 mAh cm-2 is obtained in the Zn||Zn cell. Furthermore, the assembled full battery demonstrates a prolonged cycle life of 2000 cycles.

2.
Chem Commun (Camb) ; 59(53): 8246-8249, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37313734

RESUMO

Herein, a novel rocking-chair aqueous AIB, based on the Ni-PBA inorganic cathode and PTO organic anode, is presented. This device showed an excellent cycle life and high efficiency, endowed with a high capacity-retention of 96.0% and coulombic efficiency (CE) of over 99% at 1 A g-1 after 5000 cycles. The environmentally friendly and ultralong-life aqueous AIBs are expected to provide new options for next-generation energy storage devices.


Assuntos
Alumínio , Fontes de Energia Elétrica , Eletrodos , Íons
3.
Sci Adv ; 9(13): eadf3992, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37000876

RESUMO

Implantable devices on the tumor tissue as a local treatment are able to work in situ, which minimizes systemic toxicities and adverse effects. Here, we demonstrated an implantable self-charging battery that can regulate tumor microenvironment persistently by the well-designed electrode redox reaction. The battery consists of biocompatible polyimide electrode and zinc electrode, which can consume oxygen sustainably during battery discharge/self-charge cycle, thus modulating hypoxia level in tumor microenvironment. The oxygen reduction in battery leads to the formation of reactive oxygen species, showing 100% prevention on tumor formation. Sustainable consumption of oxygen causes adequate intratumoral hypoxic conditions over the course of 14 days, which is helpful for the hypoxia-activated prodrugs (HAPs) to kill tumor cells. The synergistic effect of the battery/HAPs can deliver more than 90% antitumor rate. Using redox reactions in electrochemical battery provides a potential approach for the tumor inhibition and regulation of tumor microenvironment.


Assuntos
Neoplasias , Pró-Fármacos , Humanos , Neoplasias/patologia , Hipóxia , Oxigênio , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Água , Microambiente Tumoral
4.
Adv Mater ; 35(13): e2206228, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36004772

RESUMO

Batteries with a Li-metal anode have recently attracted extensive attention from the battery communities owing to their high energy density. However, severe dendrite growth hinders their practical applications. More seriously, when Li dendrites pierce the separators and trigger short circuit in a highly flammable organic electrolyte, the results would be catastrophic. Although the issues of growth of Li dendrites have been almost addressed by various methods, the highly flammable nature of conventional organic liquid electrolytes is still a lingering fear facing high-energy-density Li-metal batteries given the possibility of thermal runaway of the high-voltage cathode. Recently, various kinds of nonflammable liquid- or solid-state electrolytes have shown great potential toward safer Li-metal batteries with minimal detrimental effect on the battery performance or even enhanced electrochemical performance. In this review, recent advances in developing nonflammable electrolyte for high-energy-density Li-metal batteries including high-concentration electrolyte, localized high-concentration electrolyte, fluorinated electrolyte, ionic liquid electrolyte, and polymer electrolyte are summarized. Then, the solvation structure of different kinds of nonflammable liquid and polymer electrolytes are analyzed to provide insight into the mechanism for dendrite suppression and fire extinguishing. Finally, guidelines for future design of nonflammable electrolyte for safer Li-metal batteries are provided.

5.
Acta Pharmaceutica Sinica ; (12): 659-671, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-965635

RESUMO

The function of the central nervous system was significantly altered under high-altitude hypoxia, and these changes lead to central nervous system disease and affected the metabolism of drugs in vivo. The blood-brain barrier is essential for maintaining central nervous system stability and plays a key role in the regulation of drug metabolism, and barrier structure and dysfunction affect drug transport to the brain. Changes in the structure and function of the blood-brain barrier and the transport of drugs across the blood-brain barrier under high-altitude hypoxia are regulated by changes in brain microvascular endothelial cells, astrocytes and pericytes, and are regulated by drug metabolism factors such as drug transporters and drug metabolizing enzymes. This article reviews the effects of high-altitude hypoxia on the structure and function of the blood-brain barrier and the effects of changes in the blood-brain barrier on drug metabolism. We investigate the regulatory effects and underlying mechanisms of the blood-brain barrier and related pathways such as transcription factors, inflammatory factors and nuclear receptors on drug transport under high-altitude hypoxia.

6.
Nanomaterials (Basel) ; 12(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35889630

RESUMO

A self-healing epoxy coating is creatively prepared by employing expired cefalexin loaded into mesoporous silica nanomaterials (MSNs) for corrosion protection of 304 stainless steel (304SS). A series of physical characterizations, including transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectrometer, and N2 adsorption-desorption isotherms, verified that the cefalexin successfully filled porous MSN. The corrosion resistance of the epoxy (EP) coating incorporated with the cefalexin@MSNs is investigated using a Tafel polarization curve and electrochemical impedance spectra (EIS) in a 3.5 wt.% NaCl solution. It is found that the EP-Cefalexin@MSNs coating has a higher self-corrosion voltage and a lower self-corrosion current density than EP coating. Moreover, the charge transfer resistance (Rct) value of Cefalexin@MSNs coating is twice that of EP coating after immersion for 24 h, indicating that the cefalexin@MSNs significantly enhance the corrosion resistance of the coating under long-duration immersion. The improved corrosion resistance is attributed to the densified adsorption of the cefalexin inhibiting the cathode corrosion reaction, providing a self-healing long-duration corrosion protection for 304SS.

7.
Mikrochim Acta ; 189(5): 208, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501498

RESUMO

S, N co-doped graphene quantum dot (S, N-GQD) materials have been composited via a one-pot pattern and used as photosensitive materials to construct a label-free photoelectrochemical (PEC) sensor. The PEC experiments show an enhanced photocurrent response toward Bisphenol A (BPA) sensing due to the increased charge transfer rate and the enhanced absorption of visible light. Compared with dark conditions, the photocurrent signal (- 0.2 V vs. SCE) is greatly increased because of the effective oxidation of BPA by photogenerated holes and the rapid electron transfer of S, N-GQDs on the PEC sensing platform. Under optimal conditions linear current response to BPA is in two ranges of 0.12-5 µM and 5-40 µM. The limit of detection is 0.04 µM (S/N = 3). The designed sensor has enduring stability and admirable interference immunity. It  provides an alternative approach for BPA determination in real samples with recoveries of 99.3-103% and  RSD of 2.0-4.1%.


Assuntos
Grafite , Pontos Quânticos , Compostos Benzidrílicos , Técnicas Eletroquímicas , Eletrodos , Fenóis
8.
J Colloid Interface Sci ; 616: 803-812, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35248967

RESUMO

Water splitting is considered as a promising candidate for renewable and sustainable energy systems, while developing efficient, inexpensive and robust bifunctional electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) still remains a challenge. Herein, the well-designed RuCoP nanoparticles embedded in nitrogen-doped polyhedron carbon (RuCoP@CN) composite is fabricated by in-situ carbonization of Co based zeolitic imidazolate framework (ZIF-67) and phosphorization. Ru-substituted phosphate is proved to be imperative for the electrochemical activity and stability of individual catalysts, which can efficiently yield the active electronic states and promote the intrinsic OER and HER activity. As a result, a current density of 10 mA cm-2 is achieved at a cell voltage as low as 1.60 V when the RuCoP@CN electrocatalyst applied for the overall water splitting, which is superior to the reported RuO2 and Pt/C couple electrode (1.64 V). The density functional theory (DFT) calculations reveal that the introduction of Ru and P atoms increase the electronic states of Co d-orbital near the Fermi level, decreasing the free energy of the hydrogen adsorption and H2O dissociation for HER and the rate-limiting step for OER in alkaline media.

9.
Chem Commun (Camb) ; 58(10): 1550-1553, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35014634

RESUMO

A novel "water in salt" electrolyte is reported for the design of a rocking-chair proton battery. In 20 M ZnCl2 + 1 M HCl electrolyte, the electrochemical proton storage performance using MoO3 is significantly improved. When coupled with a Ni-PBA cathode, the device exhibits a good cycling stability of 76.1% after 400 cycles. This work opens a new avenue for designing low-cost "water in salt" electrolytes for aqueous proton electrochemistry.

11.
Nanomaterials (Basel) ; 11(12)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34947522

RESUMO

It is well-known that platinum (Pt) is still the preferred material of anode catalyst in ethanol oxidation, however, the prohibitive high cost and CO poisoning of Pt metal impede the commercialization of fuel cells. Therefore, improving the utilization rate of catalysts and reduce the cost of catalyst become one of the most concerned focus in the construction of fuel cells. In this work, the Pt-based catalysts are synthesized by using different content of sodium dodecyl sulfate (SDS) modified-Ti3C2Tx support, and the dispersion regulation function of SDS modified-Ti3C2Tx supported on Pt nanoparticles is investigated. The structure, composition and morphology of different catalysts are characterized by X-ray diffraction (XRD), X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and high-resolution TEM, respectively. It is found that the Pt nanoparticles in pure Ti3C2Tx surface are serious aggregated and show poor dispersion, whereas the Pt nanoparticles in SDS modified-Ti3C2Tx have a better dispersion. The electrochemical results revealed that SDS modified-Ti3C2Tx supported Pt nanoparticles has higher electrocatalytic activity and stability in both acidic and alkaline ethanol oxidation when the dosage of SDS increases to 100 mg. These findings indicate that the SDS-Ti3C2Tx/Pt catalysts show a promising future of potential applications in fuel cells with modification of Ti3C2Tx support.

12.
ACS Appl Mater Interfaces ; 13(49): 58818-58826, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34846135

RESUMO

Organic carbonyl electrode materials have shown a great potential in various rechargeable batteries but limited by the problems of poor cycling and rate performance owing to their high solubility in aqueous electrolytes and low conductivity. To address these problems, the 9,10-phenanthraquinone (PQ)@active carbon (AC) composite fabricated by melting PQ molecules into porous AC is considered as a superstable cathode material for aqueous zinc batteries. The introduction of AC improves the structural stability and restrains the PQ dissolution in an aqueous electrolyte. As a result, the PQ@AC composite electrode delivers a reversible discharge capacity of 150.0 mA h g-1 at a current density of 0.1 A g-1, and it also features an unprecedented cycling performance of 36 000 cycles with a capacity retention of 96.3% at 5 A g-1. Moreover, the Zn2+ and H+ in an aqueous electrolyte are verified to co-insert into the PQ@AC composite electrode using various ex situ characterizations and electrochemical test. This strategy provides a new avenue for organic carbonyl compounds with quinone substructures to improve their electrochemical performance of other batteries.

13.
J Colloid Interface Sci ; 602: 222-231, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34119759

RESUMO

Design of highly active and stable non-precious electrocatalysts towards hydrogen evolution reaction (HER) is a hot research topic in low cost, clean and sustainable hydrogen energy field, yet remaining the important challenge caused by the sluggish reaction kinetics for water-alkali electrolyzers. Herein, a robust electrocatalyst is proposed by designing a novel sub-nanometer of copper and ruthenium bimetallic phosphide nanoclusters (RuxCuyP2) supported on a graphited carbon nanofibers (CNF). Uniform RuxCuyP2 (~1.90 nm) on the surface of CNF are obtained by introducing the dispersed Ru, thereby improving the intrinsic activity for HER. On optimizing the Ru ratio, the (x = y = 1) RuCuP2/CNF catalyst exhibits an excellent HER electroactivity with an overpotential of 10 mV in 1.0 M NaOH electrolyte to produce 10 mA cm-2 current density, which is lower than commercial 20% Pt/C in alkaline solution. Moreover, the kinetic study demonstrated that electrochemical activation energies for HER of RuCuP2/CNF is 20.7 kJ mol-1 highest among different ratio bimetallic phosphide. This simple, cost-effective, and environmentally friendly methodology can pave the way for exploitation of bimetallic phosphide nanoclusters for catalyst design.

14.
Acta Pharmaceutica Sinica ; (12): 50-60, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-872600

RESUMO

The function of circulatory system, nervous system and endocrine system is significantly changed in hypoxic environments. These changes affect the absorption, distribution, metabolism, and excretion of drugs in the body. Drug metabolizing enzymes and transporters are the main factors affecting drug metabolism; microRNA (miRNA) can act directly on drug metabolizing enzymes and transporters and can regulate their genes through hypoxia-inducible factor, inflammatory cytokines, and nuclear receptors. This article reviews the effect of hypoxia on drug metabolizing enzymes and transporters and the mechanisms by which miRNA modulates these proteins and their expression during hypoxia.

15.
Acta Pharmaceutica Sinica ; (12): 1100-1108, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-886980

RESUMO

The structure and diversity of the intestinal flora in rats exposed to high altitude hypoxia was investigated. Animal experiments strictly follow the regulations of Medical Laboratory Animal Ethics Committee of Qinghai University, School of Medicine. SD rats were randomly divided into a control group, a moderate altitude hypoxia group, and a high altitude hypoxia group. The pH value of the feces was measured and histopathological changes in the small intestine were determined by HE staining, and the intestinal flora were characterized by 16S rDNA high throughput sequencing technology on the 3rd, 7th, 15th, and 30th day of hypoxia exposure. Compared with the control group, the fecal pH value of rats in the moderate altitude hypoxia group and the high altitude hypoxia group was decreased significantly. The lamina propria and submucosa capillaries were slightly dilated and congested on the 3rd day in the moderate altitude hypoxia group. In the high altitude hypoxia group the submembrane capillaries were dilated and congested, the lamina propria of the mucosa showed mild edema, and the lymphatic vessels were dilated on the 7th day. The composition and diversity of intestinal flora in these rats changed significantly with prolonged exposure to the high altitude hypoxic environment. A total of 35 phyla, 87 classes, 205 orders, 337 families, 638 genera, and 256 species were annotated in the three groups of rats, including Firmicutes, Clostridia, Clostridiales, Ruminococcaceae, Akkermansia, and Lactobacillus_murinus. Compared with the control group, the intestinal flora of the hypoxic groups showed the most significant changes by the 15th day. There were 9 microbiota of gut microorganisms with relative abundance in the moderate altitude hypoxia group, of which Rikenellaceae_RC9_gut_group bacteria was the most common, there were 19 different microbiota of gut microorganisms with higher relative abundance in the high altitude hypoxia group, of which Ruminococcaceae bacteria was the most common. The results of this study indicate significant changes in the intestinal flora with high altitude hypoxia, and establish a foundation for further research on the initiation and development of diseases and drug metabolism in high altitude hypoxia.

16.
Adv Mater ; 32(16): e2000338, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32141139

RESUMO

The newly emerged aqueous Zn-organic batteries are attracting extensive attention as a promising candidate for energy storage. However, most of them suffer from the unstable and/or soluble nature of organic molecules, showing limited cycle life (≤3000 cycles) that is far away from the requirement (10 000 cycles) for grid-scale energy storage. Here, a new aqueous zinc battery is proposed by using sulfur heterocyclic quinone dibenzo[b,i]thianthrene-5,7,12,14-tetraone (DTT) as the cathode. The cell shows a high reversible capacity of 210.9 mAh gDTT -1 at 50 mA gDTT -1 with a high mass loading of 5 mgDTT cm-2 , along with a fast kinetics for charge storage. Electrochemical measurements, ex situ analyses, and density functional theory calculation successfully demonstrate that the DTT electrode can simultaneously store both protons (H+ ) and Zn2+ to form DTT2 (H+ )4 (Zn2+ ), where Zn2+ is bound to the carboxyl groups from the adjacent DTT molecules with improved stability. Benefitting from the improved molecular stability and the inherent low solubility of DTT and related discharge products, the DTT//Zn full cell exhibits a superlong life of 23 000 cycles with a capacity retention of 83.8%, which is much superior to previous reports.

17.
ACS Appl Mater Interfaces ; 11(23): 20796-20803, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31090395

RESUMO

Aqueous rechargeable zinc batteries (ARZBs) are desirable for energy storage devices owing to their low cost and abundance of the Zn anode, but their further development is limited by a dearth of ideal cathode materials that can simultaneously possess high capacity and stability. Herein, we employ a layered structure of ammonium vanadium bronze (NH4)0.5V2O5 as the cathode material for ARZBs. The large interlayer distance supported by the NH4+ insertion not only facilitates the Zn2+-ion intercalation/deintercalation but also improves the electrochemical stability in ARZBs. As a result, the layered structural (NH4)0.5V2O5 cathode delivers a high capacity up to 418.4 mA h g-1 at a current density of 0.1 A g-1. A reversible capacity of 248.8 mA h g-1 is still retained after 2000 cycles and a capacity retention of 91.4% was maintained at 5 A g-1. Furthermore, in comparison with previously reported Zn-ion batteries, the Zn/(NH4)0.5V2O5 battery achieves a prominent high energy density of 418.4 W h kg-1 while delivering a high power density of 100 W kg-1. The results would enlighten and push the ammonium vanadium compounds to a brand new stage for the application of aqueous batteries.

18.
ACS Appl Mater Interfaces ; 11(15): 14085-14094, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30942998

RESUMO

Non-noble metal-based bifunctional electrocatalysts for both oxygen reduction reactions (ORRs) and oxygen evolution reactions (OERs) are an essential component of high-performance rechargeable Zn-air batteries (ZABs). Herein, we report a novel and simple method for preparing Co9S8 nanoparticles embedded in N and S codoped carbon materials with aid of carbon dots (CDs). CDs play a key role in distributing Co9S8 nanoparticles in the matrix uniformly and enhancing the specific surface area and the electric conductivity simultaneously. The obtained Co9S8/CD@NSC exhibits an excellent ORR and OER bifunctional catalytic activity and a great long-term durability, with a half-wave potential of 0.84 V versus reversible hydrogen electrode (RHE) for the ORR and a low potential of 1.62 V versus RHE at 10 mA cm-2, which outperform the popular Pt/C and RuO2 commercial catalysts. Moreover, the Co9S8/CD@NSC catalyst also displays a superior activity and cycling stability as a cathode material in ZABs, which is far better than Pt/C + RuO2 mixture catalysts. Such a ZAB shows a low charge/discharge voltage gap of 0.62 V and great cycling stability over 125 h at 10 mA cm-2.

19.
Angew Chem Int Ed Engl ; 58(17): 5623-5627, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30821403

RESUMO

Lithium metal is an ideal anode for high-energy rechargeable batteries at low temperature, yet hindered by the electrochemical instability with the electrolyte. Concentrated electrolytes can improve the oxidative/reductive stability, but encounter high viscosity. Herein, a co-solvent formulation was designed to resolve the dilemma. By adding electrochemically "inert" dichloromethane (DCM) as a diluent in concentrated ethyl acetate (EA)-based electrolyte, the co-solvent electrolyte demonstrated a high ionic conductivity (0.6 mS cm-1 ), low viscosity (0.35 Pa s), and wide range of potential window (0-4.85 V) at -70 °C. Spectral characterizations and simulations show these unique properties are associated with the co-solvation structure, in which high-concentration clusters of salt in the EA solvent were surrounded by mobile DCM diluent. Overall, this novel electrolyte enabled rechargeable metallic Li battery with high energy (178 Wh kg-1 ) and power (2877 W kg-1 ) at -70 °C.

20.
Sci Bull (Beijing) ; 64(23): 1780-1787, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36659537

RESUMO

As an effective energy storage technology, rechargeable batteries have long been considered as a promising solution for grid integration of intermittent renewables (such as solar and wind energy). However, their wide application is still limited by safety issue and high cost. Herein, a new battery chemistry is proposed to satisfy the requirements of grid energy storage. We report a simple Cu-Mn battery, which is composed of two separated current collectors in an H2SO4-CuSO4-MnSO4 electrolyte without using any membrane. The Cu-Mn battery shows an energy density of 40.8 Wh L-1, a super-long life of 10,000 cycles (without obvious capacity decay) and negligible self-discharge. And the capital cost of US$ 11.9 kWh-1 based on electrolyte is lower than any previous batteries. More importantly, the battery can still work smoothly during thermal abuse test and drill-through test, showing high safe nature. Furthermore, a combination system integrating the Cu-Mn battery and hydrogen evolution is also proposed, which is able to avoid the generation of explosive H2/O2 mixture, and presents an efficient approach for grid energy storage and conversion.

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