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1.
Adv Mater ; : e2404796, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809576

RESUMO

Aqueous Zn batteries are promising for large-scale energy storage but are plagued by the lack of high-performance cathode materials that enable high specific capacity, ultrafast charging, and outstanding cycling stability. Here, a laser-scribed nano-vanadium oxide (LNVO) cathode is designed that can simultaneously achieve these properties. The material stores charge through Faradaic redox reactions on/near the surface at fast rates owing to the small grain size of vanadium oxide and interpenetrating 3D graphene network, displaying a surface-controlled capacity contribution (90%-98%). Multiple characterization techniques unambiguously reveal that zinc and hydronium ions co-insert with minimal lattice change upon cycling. It is demonstrated that a high specific capacity of 553 mAh g-1 is achieved at 0.1 A g-1, and an impressive 264 mAh g-1 capacity is retained at 100 A g-1 within 10 s, showing excellent rate capability. The LNVO/Zn can also reach >90% capacity retention after 3000 cycles at a high rate of 30 A g-1, as well as achieving both high energy (369 Wh kg-1) and power densities (56306 W kg-1). Moreover, the LNVO cathode retains its excellent cycling performance when integrated into quasi-solid-state pouch cells, further demonstrating mechanical stability and its potential for practical application in wearable and grid-scale applications.

2.
Nanoscale Horiz ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682321

RESUMO

Aqueous lithium-ion batteries (LIBs) have received increasing attention as a promising solution for stationary energy storage systems due to their low environmental impact, non-flammability and low cost. Despite recent progress in electrolyte development and cathode manufacturing, the lack of anode materials with high specific capacity presents difficult challenges for a wide range of applications. In this study, we propose a novel synthetic strategy to fabricate a pseudocapacitive V2O5/graphene composite as a highly functional anode material for aqueous LIBs. The designed synthesis combines a fast laser-scribing step with controlled calcination to tune the morphology and oxidation state of the electrochemically active vanadium oxide species while obtaining a highly conductive graphene scaffold. The optimized V2O5/graphene anode shows an outstanding specific capacity of 158 mA h g-1 in three-electrode measurements. When the V2O5/graphene anode is paired with an LiMn2O4 cathode, the charge storage mechanism of the full cell is revealed to be dominantly surface-controlled, resulting in remarkable rate performance. Specifically, the full cell can reach a specific capacity of 151 and 107 mA h (g anode)-1 at C/6 and 3C, respectively. Moreover, this hybrid battery can achieve a high power density and an energy density of 650 W kg-1 at 15.6 W h kg-1 and 81.5 W h kg-1 at 13.6 W kg-1, respectively, outperforming most aqueous LIBs reported in the literature. This innovative strategy provides a pathway to incorporate pseudocapacitive electrodes for improving aqueous lithium-ion storage systems, enabling safe operation of large-scale energy storage without compromising their electrochemical performance.

3.
Langmuir ; 40(11): 5809-5817, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38445621

RESUMO

A dielectric liquid microlens array (LMA) with a tunable focal length was fabricated by using a microdroplet array generated through the dip-coating method. The process began with treating the octadecyltrichlorosilane (OTS) layer with selective UV/O3 irradiation for 20 min to establish a hydrophilic-hydrophobic patterning surface. The substrate was subsequently immersed in glycerol and then withdrawn at a constant rate to create a microdroplet array. Upon filling the cell with matching oil (SL5267) and placing it within a square array of a 200 µm diameter glycerol microdroplet array, the LMA was produced. The focal length ranged from approximately -0.96 to -0.3 mm within a voltage range of 0 to 60 Vrms. The glycerol microdroplets, characterized by their shapes, sizes, curvatures, and filling factors, can be precisely controlled by designing an OTS patterning or adjusting the dip-coating speed. This approach offers a rapid and high-throughput method for preparation. Our approach to fabricating tunable LMA offers several advantages, including simplicity of fabrication, uniform structural properties, cost-effectiveness, polarization independence, and excellent optical performance. These focus-tunable LMAs hold significant potential for applications in image processing, 3D displays, medical endoscopy, and military technologies.

4.
Small ; : e2305921, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38342674

RESUMO

Silicon has gained significant attention as a lithium-ion battery anode material due to its high theoretical capacity compared to conventional graphite. Unfortunately, silicon anodes suffer from poor cycling performance caused by their extreme volume change during lithiation and de-lithiation. Compositing silicon particles with 2D carbon materials, such as graphene, can help mitigate this problem. However, an unaddressed challenge remains: a simple, inexpensive synthesis of Si/graphene composites. Here, a one-step laser-scribing method is proposed as a straightforward, rapid (≈3 min), scalable, and less-energy-consuming (≈5 W for a few minutes under air) process to prepare Si/laser-scribed graphene (LSG) composites. In this research, two types of Si particles, Si nanoparticles (SiNPs) and Si microparticles (SiMPs), are used. The rate performance is improved after laser scribing: SiNP/LSG retains 827.6 mAh g-1 at 2.0 A gSi+C -1 , while SiNP/GO (before laser scribing) retains only 463.8 mAh g-1 . This can be attributed to the fast ion transport within the well-exfoliated 3D graphene network formed by laser scribing. The cyclability is also improved: SiNP/LSG retains 88.3% capacity after 100 cycles at 2.0 A gSi+C -1 , while SiNP/GO retains only 57.0%. The same trend is found for SiMPs: the SiMP/LSG shows better rate and cycling performance than SiMP/GO composites.

5.
Adv Mater ; 36(3): e2306145, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37903216

RESUMO

Rechargeability in zinc (Zn) batteries is limited by anode irreversibility. The practical lean electrolytes exacerbate the issue, compromising the cost benefits of zinc batteries for large-scale energy storage. In this study, a zinc-coordinated interphase is developed to avoid chemical corrosion and stabilize zinc anodes. The interphase promotes Zn2+ ions to selectively bind with histidine and carboxylate ligands, creating a coordination environment with high affinity and fast diffusion due to thermodynamic stability and kinetic lability. Experiments and simulations indicate that interphase regulates dendrite-free electrodeposition and reduces side reactions. Implementing such labile coordination interphase results in increased cycling at 20 mA cm-2 and high reversibility of dendrite-free zinc plating/stripping for over 200 hours. A Zn||LiMn2 O4 cell with 74.7 mWh g-1 energy density and 99.7% Coulombic efficiency after 500 cycles realized enhanced reversibility using the labile coordination interphase. A lean-electrolyte full cell using only 10 µL mAh-1 electrolyte is also demonstrated with an elongated lifespan of 100 cycles, five times longer than bare Zn anodes. The cell offers a higher energy density than most existing aqueous batteries. This study presents a proof-of-concept design for low-electrolyte, high-energy-density batteries by modulating coordination interphases on Zn anodes.

6.
Macromol Rapid Commun ; 45(1): e2300237, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37232260

RESUMO

Conducting polymers like polyaniline (PANI) are promising pseudocapacitive electrode materials, yet experience instability in cycling performance. Since polymers often degrade into oligomers, short chain length anilines have been developed to improve the cycling stability of PANI-based supercapacitors. However, the capacitance degradation mechanisms of aniline oligomer-based materials have not been systematically investigated and are little understood. Herein, two composite electrodes based on aniline trimers (AT) and carbon nanotubes (CNTs) are studied as model systems and evaluated at both pre-cycling and post-cycling states through physicochemical and electrochemical characterizations. The favorable effect of covalent bonding between AT and CNTs is confirmed to enhance cycling stability by preventing the detachment of aniline trimer and preserving the electrode microstructure throughout the charge/discharge cycling process. In addition, higher porosity has a positive effect on electron/ion transfer and the adaptation to volumetric changes, resulting in higher conductivity and extended cycle life. This work provides insights into the mechanism of enhanced cycling stability of aniline oligomers, indicating design features for aniline oligomer electrode materials to improve their electrochemical performance.


Assuntos
Nanotubos de Carbono , Polímeros , Polímeros/química , Nanotubos de Carbono/química , Compostos de Anilina/química
7.
Mater Horiz ; 11(3): 688-699, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-37990914

RESUMO

The development of potent pseudocapacitive charge storage materials has emerged as an effective solution for closing the gap between high-energy density batteries and high-power density and long-lasting electrical double-layer capacitors. Sulfonyl compounds are ideal candidates owing to their rapid and reversible redox reactions. However, structural instability and low electrical conductivity hinder their practical application as electrode materials. This work addresses these challenges using a fast and clean laser process to interconnect sulfonated carbon nanodots into functionalized porous carbon frameworks. In this bottom-up approach, the resulting laser-converted three-dimensional (3D) turbostratic carbon foams serve as high-surface-area, conductive scaffolds for redox-active sulfonyl groups. This design enables efficient faradaic processes using pendant sulfonyl groups, leading to a high specific capacitance of 157.6 F g-1 due to the fast reversible redox reactions of sulfonyl moieties. Even at 20 A g-1, the capacitance remained at 78.4% due to the uniform distribution of redox-active sites on the graphitic domains. Additionally, the 3D-tsSC300 electrode showed remarkable cycling stability of >15 000 cycles. The dominant capacitive processes and kinetics were analysed using extensive electrochemical characterizations. Furthermore, we successfully used 3D-tsSC300 in flexible solid-state supercapacitors, achieving a high specific capacitance of up to 17.4 mF cm-2 and retaining 91.6% of the initial capacitance after 20 000 cycles of charge and discharge coupled with 90° bending tests. Additionally, an as-assembled flexible all-solid-state symmetric supercapacitor exhibits a high energy density of 12.6 mW h cm-3 at a high power density of 766.2 W cm-3, both normalized by the volumes of the full device, which is comparable or better than state-of-the-art commercial pseudocapacitors and hybrid capacitors. The integrated supercapacitor provides a wide potential window of 2.0 V using a serial circuit, showing great promise for metal-free energy storage devices.

8.
Nano Lett ; 23(8): 3317-3325, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37039594

RESUMO

Long cycle life and high energy/power density are imperative to energy storage systems. Polyaniline (PANI) has shown great potential as an electrode material but is limited by poor cycling and rate performance. We present a molecular design approach of binding short-chain aniline trimers (ATs) and carbon nanotubes (CNTs) through the formation of amide covalent linkages enabled by a simple laser scribing technique. The covalently coupled AT/CNT (cc-AT/CNT) composite retains 80% of its original capacitance after 20 000 charge/discharge cycles, which readily outperforms long-chain PANI/CNT composites without covalent connections. The compact AT/CNT heterointerfaces produce fast charge/discharge kinetics and excellent rate capability. The flexible symmetric quasi-solid-state devices can be stably cycled beyond 50 000 cycles, at least 5 times longer than most PANI/CNT-based symmetric supercapacitors reported to date. This molecular design of durable conducting polymer-based electrode materials enabled by laser irradiation presents a feasible approach toward robust advanced energy storage devices.

9.
Endocrinol Metab (Seoul) ; 38(1): 156-173, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36604945

RESUMO

BACKGRUOUND: Evidence has revealed the involvement of microRNAs (miRNAs) in modulating osteogenic differentiation, implying the promise of miRNA-based therapies for treating osteoporosis. This study investigated whether miR-181a-5p influences osteogenic differentiation and bone formation and aimed to establish the mechanisms in depth. METHODS: Clinical serum samples were obtained from osteoporosis patients, and MC3T3-E1 cells were treated with osteogenic induction medium (OIM) to induce osteogenic differentiation. miR-181a-5p-, Runt-related transcription factor 1 (Runx1)-, and/or allograft inflammatory factor-1 (AIF-1)-associated oligonucleotides or vectors were transfected into MC3T3-E1 cells to explore their function in relation to the number of calcified nodules, alkaline phosphatase (ALP) staining and activity, expression levels of osteogenesis-related proteins, and apoptosis. Luciferase activity, RNA immunoprecipitation, and chromatin immunoprecipitation assays were employed to validate the binding relationship between miR-181a-5p and Runx1, and the transcriptional regulatory relationship between Runx1 and AIF-1. Ovariectomy (OVX)-induced mice were injected with a miR-181a-5p antagonist for in vivo verification. RESULTS: miR-181a-5p was highly expressed in the serum of osteoporosis patients. OIM treatment decreased miR-181a-5p and AIF-1 expression, but promoted Runx1 expression in MC3T-E1 cells. Meanwhile, upregulated miR-181a-5p suppressed OIM-induced increases in calcified nodules, ALP content, and osteogenesis-related protein expression. Mechanically, miR-181a-5p targeted Runx1, which acted as a transcription factor to negatively modulate AIF-1 expression. Downregulated Runx1 suppressed the miR-181a-5p inhibitor-mediated promotion of osteogenic differentiation, and downregulated AIF-1 reversed the miR-181a-5p mimic-induced inhibition of osteogenic differentiation. Tail vein injection of a miR-181a-5p antagonist induced bone formation in OVX-induced osteoporotic mice. CONCLUSION: In conclusion, miR-181a-5p affects osteogenic differentiation and bone formation partially via the modulation of the Runx1/AIF-1 axis.


Assuntos
MicroRNAs , Osteoporose , Animais , Feminino , Camundongos , Diferenciação Celular/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Osteogênese/genética , Osteoporose/genética
10.
Front Endocrinol (Lausanne) ; 13: 917356, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937793

RESUMO

Increasing evidence suggests that aldosterone (Aldo) plays an essential role in vascular calcification which is a serious threat to cardiovascular disease (CVD) developed from chronic kidney disease (CKD). However, the exact pathogenesis of vascular calcification is still unclear. First, we established CKD-associated vascular calcification mice model and knockout mice model to investigate the causal relationship between allograft inflammatory factor 1 (AIF-1) and vascular calcification. Then, endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) co-culture experiments were performed to further explore the mechanisms of calcification. The results of the Aldo intervention mice model and transgenic mice model showed that Aldo could cause calcification by increasing the AIF-1 level. The results of in vitro co-culture model of ECs and VSMCs showed that AIF-1 silence in ECs may alleviate Aldo-induced calcification of VSMCs. In conclusion, our study indicated that Aldo may induce vascular calcification related to chronic renal failure via the AIF-1 pathway which may provide a potential therapeutic target.


Assuntos
Insuficiência Renal Crônica , Calcificação Vascular , Aldosterona/metabolismo , Animais , Técnicas de Cocultura , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/metabolismo , Calcificação Vascular/induzido quimicamente
11.
Nano Lett ; 21(22): 9485-9493, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34738821

RESUMO

Because of increasing interest in environmentally benign supercapacitors, earth-abundant biopolymers have found their way into value-added applications. Herein, a promising nanocomposite based on an interpenetrating network of polyaniline and sulfonated lignin (lignosulfonate, LS) is presented. On the basis of an appropriate regulation of the nucleation kinetics and growth behavior via applying a series of rationally designed potential pulse patterns, a uniform PANI-LS film is achieved. On the basis of the fast rate of H+ insertion-deinsertion kinetics, rather than the slow SO42- doping-dedoping process, the PANI-LS nanocomposite delivers specific capacitance of 1200 F g-1 at 1 A g-1 surpassing the best conducting polymer-lignin supercapacitors known. A symmetric PANI-LS||PANI-LS device delivers a high specific energy of 21.2 W h kg-1, an outstanding specific power of 26.0 kW kg-1, along with superb flexibility and excellent cycling stability. Thus, combining charge storage attributes of polyaniline and lignosulfonate enables a waste-to-wealth approach to improve the supercapacitive performance of polyaniline.


Assuntos
Lignina , Nanocompostos , Compostos de Anilina , Capacitância Elétrica
12.
Small ; 17(48): e2006875, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34048633

RESUMO

Technological breakthroughs in energy storage are being driven by the development of next-generation supercapacitors with favorable features besides high-power density and cycling stability. In this innovation, graphene and its derived materials play an active role. Here, the research status of graphene supercapacitors is analyzed. Recent progress is outlined in graphene assembly, exfoliation, and processing techniques. In addition, electrochemical and electrical attributes that are increasingly valued in next-generation supercapacitors are highlighted along with a summary of the latest research addressing chemical modification of graphene and its derivatives for future supercapacitors. The challenges and solutions discussed in the review hopefully will shed light on the commercialization of graphene and a broader genre of 2D materials in energy storage applications.


Assuntos
Grafite , Eletricidade
13.
J Endocrinol ; 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30557853

RESUMO

Puberty onset is a complex trait regulated by multiple genetic and environmental factors. In this study, we narrowed a puberty related QTL region down to a 1.7 Mb region on chromosome X in female mice and inferred miR-505-3p as the functional gene. We conducted ectopic expression of miR-505-3p in the hypothalamus of prepubertal female mice through lentivirus-mediated orthotopic injection. The impact of miR-505-3p on female puberty was evaluated by the measurement of pubertal/reproduction events and histological analysis. The results showed that female mice with overexpression of miR-505-3p in the hypothalamus manifested later puberty onset timing both in vaginal opening and ovary maturation, followed by weaker fertility lying in the longer interval time between mating and delivery, higher abortion rate and smaller litter size. We also constructed miR-505-3p knockout mice by CRISPR/Cas9 technology. MiR-505-3p knockout female mice showed earlier vaginal opening timing, higher serum gonadotrophin and higher expression of puberty-related gene in the hypothalamus than their wild type littermates. Srsf1 was proved to be the target gene of miR-505-3p that played the major role in this process. The results of RNA Immunoprecipitation-sequencing showed that SRSF1 (or SF2), the protein product of Srsf1 gene, mainly bound to ribosome protein (RP) mRNAs in GT1-7 cells. The collective evidence implied that miR-505-3p/SRSF1/RP could play a role in the sexual maturation regulation of mammals.

14.
Biomed Res Int ; 2017: 5716204, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28691026

RESUMO

BACKGROUND: This study investigated whether quercetin could alleviate vascular calcification in experimental chronic renal failure rats induced by adenine. METHODS: 32 adult male Wistar rats were randomly divided into 4 groups fed normal diet, normal diet with quercetin supplementation (25 mg/kg·BW/d), 0.75% adenine diet, or adenine diet with quercetin supplementation. All rats were sacrificed after 6 weeks of intervention. Serum renal functions biomarkers and oxidative stress biomarkers were measured and status of vascular calcification in aorta was assessed. Furthermore, the induced nitric oxide synthase (iNOS)/p38 mitogen activated protein kinase (p38MAPK) pathway was determined to explore the potential mechanism. RESULTS: Adenine successfully induced renal failure and vascular calcification in rat model. Quercetin supplementation reversed unfavorable changes of phosphorous, uric acid (UA) and creatinine levels, malonaldehyde (MDA) content, and superoxide dismutase (SOD) activity in serum and the increases of calcium and alkaline phosphatase (ALP) activity in the aorta (P < 0.05) and attenuated calcification and calcium accumulation in the medial layer of vasculature in histopathology. Western blot analysis showed that iNOS/p38MAPK pathway was normalized by the quercetin supplementation. CONCLUSIONS: Quercetin exerted a protective effect on vascular calcification in adenine-induced chronic renal failure rats, possibly through the modulation of oxidative stress and iNOs/p38MAPK pathway.


Assuntos
Falência Renal Crônica/induzido quimicamente , Falência Renal Crônica/tratamento farmacológico , Estresse Oxidativo , Quercetina/uso terapêutico , Calcificação Vascular/tratamento farmacológico , Calcificação Vascular/patologia , Adenina , Fosfatase Alcalina/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/enzimologia , Aorta/patologia , Aorta/fisiopatologia , Biomarcadores/sangue , Cálcio/sangue , Rim/efeitos dos fármacos , Rim/fisiopatologia , Falência Renal Crônica/patologia , Falência Renal Crônica/fisiopatologia , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fósforo/sangue , Quercetina/farmacologia , Ratos Wistar , Calcificação Vascular/sangue , Calcificação Vascular/fisiopatologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Vascul Pharmacol ; 88: 21-29, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27932069

RESUMO

Vascular calcification is a strong independent predictor of increased cardiovascular morbidity and mortality and has a high prevalence among patients with chronic kidney disease. The present study investigated the effects of quercetin on vascular calcification caused by oxidative stress and abnormal mitochondrial dynamics both in vitro and in vivo. Calcifying vascular smooth muscle cells (VSMCs) treated with inorganic phosphate (Pi) exhibited mitochondrial dysfunction, as demonstrated by decreased mitochondrial potential and ATP production. Disruption of mitochondrial structural integrity was also observed in a rat model of adenine-induced aortic calcification. Increased production of reactive oxygen species, enhanced expression and phosphorylation of Drp1, and excessive mitochondrial fragmentation were also observed in Pi-treated VSMCs. These effects were accompanied by mitochondria-dependent apoptotic events, including release of cytochrome c from the mitochondria into the cytosol and subsequent activation of caspase-3. Quercetin was shown to block Pi-induced apoptosis and calcification of VSMCs by inhibiting oxidative stress and decreasing mitochondrial fission by inhibiting the expression and phosphorylation of Drp1. Quercetin also significantly ameliorated adenine-induced aortic calcification in rats. In summary, our findings suggest that quercetin attenuates calcification by reducing apoptosis of VSMCs by blocking oxidative stress and inhibiting mitochondrial fission.


Assuntos
Dinâmica Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quercetina/farmacologia , Calcificação Vascular/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Citocromos c/metabolismo , Modelos Animais de Doenças , Masculino , Mitocôndrias/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Calcificação Vascular/patologia
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