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1.
Nat Genet ; 55(12): 2243-2254, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38036791

RESUMEN

Broomcorn millet (Panicum miliaceum L.) is an orphan crop with the potential to improve cereal production and quality, and ensure food security. Here we present the genetic variations, population structure and diversity of a diverse worldwide collection of 516 broomcorn millet genomes. Population analysis indicated that the domesticated broomcorn millet originated from its wild progenitor in China. We then constructed a graph-based pangenome of broomcorn millet based on long-read de novo genome assemblies of 32 representative accessions. Our analysis revealed that the structural variations were highly associated with transposable elements, which influenced gene expression when located in the coding or regulatory regions. We also identified 139 loci associated with 31 key domestication and agronomic traits, including candidate genes and superior haplotypes, such as LG1, for panicle architecture. Thus, the study's findings provide foundational resources for developing genomics-assisted breeding programs in broomcorn millet.


Asunto(s)
Panicum , Panicum/genética , Panicum/química , Domesticación , Fitomejoramiento , Fenotipo , Genómica
2.
ACS Omega ; 8(17): 15564-15585, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37151547

RESUMEN

Most of the traditional extended Kalman filter algorithms for the co-estimation of SOC and capacity of lithium-ion batteries are designed based on the minimum mean square error (MMSE) criterion, which may show superior performance in Gaussian noise scenes. However, due to the complexity of the battery operating environment, it is likely to face non-Gaussian noise (especially outlier noise), at which time the performance of the traditional extended Kalman filter algorithms will be seriously weakened. To solve the above problems, this paper first proposes a double extended Kalman filter algorithm based on weighted multi-innovation and weighted maximum correlation entropy (WMI-WMCC-DEKF) for the co-estimation of battery SOC and capacity. In this paper, the performance of the target algorithm is verified and compared by generating different types of noise from three noise models: weak Gaussian mixture noise, strong Gaussian mixture noise, and outlier noise. The maximum absolute error value (MAE) and root mean square error value (RMSE) of the WMI-WMCC-DEKF algorithm can achieve the highest performance improvement of 69.3 and 84.2% (SOC), 61.3, and 94.2% (capacity), respectively. The experimental results fully prove that the target algorithm has excellent performance against three kinds of noises.

3.
Dalton Trans ; 52(9): 2631-2640, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36744545

RESUMEN

Diabetics often prick their fingertips to measure the glucose levels in their blood. However, this traditional method not only causes prolonged pain but also increases the risk of infection. Hence, in this study, a non-invasive flexible glucose biosensor with high sensitivity was fabricated. Specifically, NiCo metal-organic frameworks (NiCo-MOFs) served as the electrode material of a micro-supercapacitor and sensing material of a glucose sensor. The electrochemical tests verified that the prominent sensitivity of the NiCo bimetal product is 1422.2 µA mM-1 cm-2. The micro-supercapacitor based on the as-fabricated NiCo-MOFs showed a high energy density of 11.5 mW h cm-2 at the power density 0.26 mW cm-2. In addition, the as-designed glucose device exhibited an excellent sensitivity of 0.31 µA µM-1. Furthermore, a flexible energy storage and glucose detection system was successfully prepared by further integrating the micro-supercapacitor and glucose sensor. The smart detector could accurately and conveniently measure the glucose concentration in sweat in real-time. Therefore, the wearable real-time sensing device displays feasible application for non-invasive glucose monitoring and health management.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Dispositivos Electrónicos Vestibles , Glucosa , Glucemia , Automonitorización de la Glucosa Sanguínea , Técnicas Biosensibles/métodos
4.
Am J Cancer Res ; 12(10): 4502-4519, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36381328

RESUMEN

Tumor metastasis is the major cause of cancer mortality; therefore, it is imperative to discover effective therapeutic drugs for anti-metastasis therapy. In the current study, we investigated whether ivermectin (IVM), an FDA-approved antiparasitic drug, could prevent cancer metastasis. Colorectal and breast cancer cell lines and a cancer cell-derived xenograft tumor metastasis model were used to investigate the anti-metastasis effect of IVM. Our results showed that IVM significantly inhibited the motility of cancer cells in vitro and tumor metastasis in vivo. Mechanistically, IVM suppressed the expressions of the migration-related proteins via inhibiting the activation of Wnt/ß-catenin/integrin ß1/FAK and the downstream signaling cascades. Our findings indicated that IVM was capable of suppressing tumor metastasis, which provided the rationale on exploring the potential clinical application of IVM in the prevention and treatment of cancer metastasis.

5.
J Orthop Translat ; 35: 87-98, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36196075

RESUMEN

Background: Sarcopenia is an age-related skeletal muscle dysfunction syndrome that is lacking validated treatments. Maximizing muscle strength in young adulthood may be a promising way to prevent sarcopenia in the elderly. The phytomolecule puerarin has been extensively used in clinical practice and reported to increase energy metabolism in skeletal muscle by directly targeting the skeletal muscle fiber. However, the bioavailability of puerarin is very poor, and almost 93% of puerarin stays in the intestine until excretion. Therefore, we hypothesize that puerarin may regulate gut microbiota to improve skeletal muscle strength and/or mass in adults. Methods: Twenty three-month old male Sprague Dawley rats were divided into two groups according to average weights, puerarin group (puerarin dissolved in 0.5% CMC-Na, 150 â€‹mg/kg/day, N â€‹= â€‹10), and control group (equal volume 0.5% CMC-Na, N â€‹= â€‹10). The treatment lasted for 8 weeks. Muscle weight, muscle fiber types and cross-sectional area (CSA), ex vivo muscle contraction test and grip strength were measured. 16S rDNA sequencing was employed to evaluate the gut microbiota composition in the sample of cecal content. Short-chain fatty acids (SCFAs) in cecal and serum were analyzed by gas chromatography-mass spectrometry. Adenosine triphosphate (ATP) concentration in skeletal muscle was also detected. Pearson's correlation was used to analyze the relations between SCFAs, ATP concentration and muscle function. Results: After puerarin treatment, grip strength, the specific twitch force, and the tetanic forces in the soleus (SOL) and extensor digitorum longus (EDL) muscle were significantly higher than those of the control group. The percentage and CSA of type II muscle fiber in EDL was higher in the puerarin group than those in the control group. Puerarin treatment significantly changed the gut microbial constitutes. Two SCFAs-productive microbiota, the families Peptococcaceae and Closteridiales, were significantly higher in the puerarin group than those in the control group, while the ratio of Prevotellaceae/Bacteroidaceae (P/B), a muscle atrophy indicator, was lower in the puerarin group. As expected, there were significant linear correlations between the concentrations of SCFAs, including cecal total SCFAs, serum n-butyric acid and total SCFAs, and skeletal muscle strength and function, including the twitch force and tetanic force of SOL and EDL, as well as the forelimb grip strength. Conclusion: In conclusion, puerarin improved the forelimb grip strength and muscle contraction function in young adult rats. The underlying mechanism may include that puerarin increased SCFAs production by regulating gut microbiota, augmented ATP synthesis and skeletal muscle strength. The translational potential of this article : Our study finds that a clinical used phytomolecule puerarin has the potential of improving skeletal muscle strength in young adult rats. As puerarin has long-term clinical experience and shows good safety, it might be a potential candidate for developing muscle strengthening agents.

6.
Adv Biol (Weinh) ; 6(12): e2200162, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36026561

RESUMEN

Treatments are lacking for sarcopenia, which is an age-related disease characterized by loss of skeletal muscle mass, strength, and/or physical performance. Icariin is a phytomolecule from herbal Epimedium, a traditional Chinese medicine widely used to treat musculoskeletal disorders for thousands of years. Here the effects of icariin against sarcopenia are investigated and the underlying mechanism is elucidated. A classic rat model of bilaterally orchiectomized (ORX) is used to induce sarcopenia. After administration for 8 weeks, compared to the control group, the forelimb grip strength, the specific tetanic forces of the soleus (SOL) and extensor digitorum longus muscle (EDL) are higher, and the fiber cross-sectional areas (CSAs) of the gastrocnemius and tibialis anterior muscle are larger in the icariin group. In addition, icariin promotes mRNA and protein expressions of myosin heavy chain (MyHC) both in SOL and EDL. Mechanistically, icariin significantly suppresses the mRNA and protein expressions of FOXO3a, atrogin-1, and MuRF-1, which are related to the degradation of myosin heavy chain. Collectively, icariin protects from sarcopenia in ORX rats characterized by enhancing grip strength and skeletal muscle contraction, as well as increasing skeletal muscle CSA by inhibiting the ubiquitination degradation of the MyHC in skeletal muscle fibers.


Asunto(s)
Flavonoides , Cadenas Pesadas de Miosina , Sarcopenia , Animales , Ratas , Contracción Muscular/fisiología , Cadenas Pesadas de Miosina/genética , ARN Mensajero/metabolismo , Sarcopenia/tratamiento farmacológico , Orquiectomía , Masculino , Flavonoides/farmacología
7.
ACS Appl Mater Interfaces ; 14(33): 37843-37852, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35947783

RESUMEN

The precise measurement of glucose level is significant for the health management of the human body. However, the existing sensitive materials and detection methods for glucose are less satisfying for practical applications. Herein, an ultrathin reticular two-dimensional nanosheets array composed of trimesic acid (H3BTC)-based bimetal metal-organic frameworks (MOFs) and carbon cloth (CC), which is constructed through a morphology control strategy, is reported for glucose sensing. Meanwhile, this nonmoving sweat glucose sensor based on a NiCo-BTC/CC electrode has been successfully prepared by a screen printing method. Benefiting from the regular and ultrathin nanosheets array, the NiCo-BTC/CC electrode has an excellent sensitivity of 2701.29 µA mM-1 cm-2, which is about 2.4 times that of its unregulated counterpart (1127.85 µA mM-1 cm-2) in the linear range 5-205 µM. In addition, an ultralow detection limit (0.09 µM, S/N = 3) and good selectivity of NiCo-BTC/CC were also obtained. The high sensitivity of the glucose sensor based on NiCo-BTC/CC electrode is 0.174 µA µM-1 (50-1000 µM). Remarkably, the preciously designed sensor is used to detect glucose concentration in sweat with a noninvasive mode, and the results are basically consistent with those of a commercial glucose device with an invasive mode. This research exhibits potential methodology for the morphology design of bimetallic MOFs nanosheets to achieve a high accuracy rate and noninvasive and timeless measurement of a glucose sensor.


Asunto(s)
Glucosa , Estructuras Metalorgánicas , Carbono , Electrodos , Humanos
8.
Artículo en Inglés | MEDLINE | ID: mdl-34601086

RESUMEN

The insects have different physiological and morphological characteristics in various developmental stages. The difference in the characteristics may be related to the different sensitivity of insects to insecticides. In avermectin resistant strain screening assay, we found that the Drosophila larvae displayed a higher sensitivity to the insecticidal effect of avermectin, compared with adults. In this study, we found that the Drosophila larvae have relatively thicker chitin layer, faster avermectin metabolism and lower P-glycoprotein (P-gp) level, when compared with the adults. Besides, the expression levels of the molecular targets of avermectin, glutamate-gated chloride channel and γ-aminobutyric acid (GABA)-gated chloride channel, are lower in the larval stage than the adult. These results suggested that lower P-gp level in the body especially in brain may be the major reason for the higher sensitivity of Drosophila larvae to the insecticide. In summary, these results shed new light on the concept that different developmental stages of insects display different sensitivity to the same insecticide, which also provided a physiological explanation of the relevant mechanism of the difference of sensitivity of insect at its larval and adult stages to insecticide.


Asunto(s)
Drosophila melanogaster/metabolismo , Resistencia a los Insecticidas , Insecticidas/toxicidad , Ivermectina/análogos & derivados , Larva/metabolismo , Animales , Ivermectina/toxicidad
9.
Drug Discov Today ; 27(3): 866-880, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34763067

RESUMEN

Friedreich's ataxia (FRDA) is caused by an intronic guanine-adenine-adenine (GAA) trinucleotide expansion in the gene encoding the frataxin protein (FXN). This triggers the transcriptional silencing of the fratxin gene (FXN) and subsequent FXN deficiency in affected cells, which accounts for the multisystemic symptoms of this condition. Current management strategies aim for symptomatic relief and no treatments can prevent disease onset or progression. Thus, research efforts have focused on targeting the molecular pathways that silence FXN and downstream pathological processes. However, progression of potential therapies into clinical use has been hindered by inconclusive clinical trials because of the small patient sample size associated with the low prevalence of this condition. Here, we discuss various molecular approaches and explore their therapeutic potential to alter the course of this progressive condition.


Asunto(s)
Ataxia de Friedreich , Adenina , Ataxia de Friedreich/complicaciones , Ataxia de Friedreich/genética , Ataxia de Friedreich/prevención & control , Humanos
10.
Nanomaterials (Basel) ; 11(10)2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34685106

RESUMEN

Although sheet-like materials have good electrochemical properties, they still suffer from agglomeration problems during the electrocatalytic process. Integrating two-dimensional building blocks into a hollow cage-like structure is considered as an effective way to prevent agglomeration. In this work, the hierarchical NiCo2O4 nanocages were successfully synthesized via coordinated etching and precipitation method combined with a post-annealing process. The nanocages are constructed through the interaction of two-dimensional NiCo2O4 nanosheets, forming a three-dimensional hollow hierarchical architecture. The three-dimensional supporting cavity effectively prevents the aggregation of NiCo2O4 nanosheets and the hollow porous feature provides amounts of channels for mass transport and electron transfer. As an electrocatalytic electrode for methanol, the NiCo2O4 nanocages-modified glassy carbon electrode exhibits a lower overpotential of 0.29 V than those of NiO nanocages (0.38 V) and Co3O4 nanocages (0.34 V) modified glassy carbon electrodes. The low overpotential is attributed to the prominent electrocatalytic dynamic issued from the three-dimensional hollow porous architecture and two-dimensional hierarchical feature of NiCo2O4 building blocks. Furthermore, the hollow porous structure provides sufficient interspace for accommodation of structural strain and volume change, leading to improved cycling stability. The NiCo2O4 nanocages-modified glassy carbon electrode still maintains 80% of its original value after 1000 consecutive cycles. The results demonstrate that the NiCo2O4 nanocages could have potential applications in the field of direct methanol fuel cells due to the synergy between two-dimensional hierarchical feature and three-dimensional hollow structure.

11.
ACS Appl Mater Interfaces ; 13(16): 18784-18791, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33849268

RESUMEN

The inorganic CsPbI3 perovskite has attracted tremendous attention in the photovoltaic fields for its chemical stability and suitable band gap. Generally, CsPbI3 solar cells with decent performances adopted high annealing temperature to form high-quality black-phase perovskite films. The high-temperature process hinders its practical application and further development. Hence, fabricating stable black-phase CsPbI3 at low temperature is imperative and necessary. In this work, a new additive p-xylilenediamine bromide (PhDMADBr) is reported to facilitate the synthesis of solution-processed, high-quality, and stable γ-CsPbI3 films at a surprisingly low temperature of 60 °C. The additive with an appropriate content can effectively improve both the film morphology and crystallinity of γ-CsPbI3 perovskite films. PhDMADBr anchors to the perovskite surface or grain boundaries as a protection through hydrogen bonding between its ammonium cations and CsPbI3. In addition, the Br element introduced by the additive passivates I- vacancies in perovskite films, resulting in the improvement of both phase stability and devices' performance. Finally, the PSCs based on the modified γ-CsPbI3 perovskite film achieve a champion efficiency of 12.71%. Moreover, the device retains 85% of its original efficiency after being kept for 1000 h.

12.
Nanotechnology ; 32(20): 205502, 2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-33524964

RESUMEN

A novel co-spray method was proposed to fabricate a reduced graphene oxide (rGO)-poly (3-hexylthiophene) (P3HT) hybrid sensing device utilizing immiscible solution for ammonia detection at room temperature. The spectrum and Scanning Electron Microscopy (SEM) results revealed uniformly crimped morphology and favorable π-π interaction for the hybrid film. The hybrid film-based sensor showed obviously enhanced ammonia sensing performance, such as increased response, reduced response time, and reinforced sensitivity, in comparison to bare rGO, P3HT, and traditional rGO/P3HT layered film-based sensors, which could be attributed to an adsorption energy barrier and the p-n heterojunction effect. The synergetic strengthened sensing mechanism is discussed. Meanwhile, recovery ratio was introduced to evaluate the abnormal baseline drift induced high-response behavior. The excellent sensing properties of the hybrid sensor indicate that the co-spray method could be an alternative process for the preparation of hetero-affinity hybrid films or functional devices.

13.
Nanoscale Res Lett ; 15(1): 194, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33001319

RESUMEN

Two-dimensional (2D) organic-inorganic perovskites as one of the most important photovoltaic material used in solar cells have attracted remarkable attention. These 2D perovskites exhibit superior environmental stability and wide tunability of their optoelectronic properties. However, their photovoltaic performance is far behind those of traditional three-dimensional (3D) perovskites. In this work, we demonstrate the power conversion efficiency (PCE) of 2D perovskite solar cells (PVSCs) is greatly improved from 3.01% for initial to 12.19% by the incorporation of PbBr2. The enhanced efficiency is attributed to superior surface quality, enhanced crystallinity, and the resulting reduced trap-state density. Furthermore, PbBr2 incorporated devices without encapsulation show excellent humidity stability, illumination stability, and thermal stability. This work provides a universal and viable avenue toward efficient and stable 2D PVSCs.

14.
Nanoscale Res Lett ; 15(1): 178, 2020 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-32936365

RESUMEN

Although the power conversion efficiency (PCE) of perovskite solar cells (PSCs) increases rapidly, there are still some issues that limit their commercialization. The perovskite is sensitive to the water molecules, increasing the difficulty in the preparation of perovskite films in ambient condition. Most high-performance PSCs based on conventional method are required to be prepared in inert atmosphere condition, which increase the fabrication cost. To fabricate the high-quality perovskite in ambient condition, we preheated the substrates and selected the proper anti-solvent. As a result, the target perovskite films show a better crystallinity compared with perovskite film prepared via the conventional one-step deposition method in ambient condition. The PSCs prepared in ambient condition yield the improved PCE of 16.89% from a PCE of 11.59%. Compared with the reference devices, the performance stability of target PSCs is much better than that of reference PSCs.

15.
ACS Appl Mater Interfaces ; 12(42): 47416-47424, 2020 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-32972139

RESUMEN

Scalable and cost-effective fabrication of three-dimensional (3D) boron carbon nitride (BCN) microspheres was first demonstrated by hydrothermal and annealing methods. In particular, the specific surface area of 3D-BCN-4 reached 1390.12 m2 g-1 and had a high hierarchical pore structure. An all-printed solid-state flexible microsupercapacitor (MSC) based on 3D-BCN-4 microspheres as an electrode material was fabricated for the first time by a screen printing method, which also provided efficacious properties. The single MSC areal capacitance reached 41.6 mF cm-2. Furthermore, the remarkable mechanical flexibility was also achieved for the device with evidence that no obvious capacitance loss occurred even upon bending to 180°, and the device had a 93.3% capacitance retention after 1000 cycles. In addition, the maximum energy density reached 0.00832 mW h cm-2, and the highest power density was 2 mW cm-2. These results show the synthesis of 3D-BCN by a facile and effective method with excellent electrochemical performance, which should provide a promising direction to wearable energy storage devices.

16.
Nanoscale Res Lett ; 15(1): 108, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32405879

RESUMEN

Steering the crystallization of two-dimensional (2D) perovskite film is an important strategy to improve the power conversion efficiency (PCE) of 2D perovskite solar cells (PVSCs). In this paper, the deionized water (H2O) additive is introduced into the perovskite precursor solution to prepare high-quality 2D perovskite films. The 2D perovskite film treated with 3% H2O shows a good surface morphology, increased crystal size, enhanced crystallinity, preferred orientation, and low defect density. The fabricated 2D PVSC with 3% H2O exhibits a higher PCE compared with that without H2O (12.15% vs 2.29%). Furthermore, the shelf stability of unsealed devices with 3% H2O under ambient environment is significantly improved. This work provides a simple method to prepare high-quality 2D perovskite films for efficient and stable 2D PVSCs.

17.
Nanoscale Res Lett ; 15(1): 36, 2020 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-32030580

RESUMEN

Construct dielectric films with high energy density and efficiency are the key factor to fabricate high-performance dielectric film capacitors. In this paper, an all organic composite film was constructed based on high dielectric polymer and linear dielectric polymer. After the optimized polycondensation reaction of a linear dielectric polymer aromatic polythiourea (ArPTU), the proper molecular weight ArPTU was obtained, which was introduced into poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (PVDF-TrFE-CFE) terpolymer for a composite dielectrics. The results indicate that the addition of ArPTU molecules reduces the dielectric loss and improves the breakdown field strength of the PVDF-TrFE-CFE effectively. For the PVDF-TrFE-CFE/ArPTU (90/10) composite film, the maximum energy density about 22.06 J/cm3 at 407.57 MV/m was achieved, and high discharge efficiency about 72% was presented. This composite material can be casted on flexible substrate easily, and PVDF-TrFE-CFE/ArPTU organic composite films having high energy density, high breakdown field strength, low dielectric loss, and higher discharge efficiency are obtained. This is an unreported exploration about high energy density organic dielectric films based on PVDF-TrFE-CFE matrix and linear polymer dielectrics, and the findings of this research can provide a simple and scalable method for producing flexible high energy density materials for energy storage devices.

18.
Nanoscale Res Lett ; 14(1): 267, 2019 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-31388867

RESUMEN

The three-dimensional (3D) porous nanostructures have shown attractive promise for flexible microsupercapacitors due to their merits of more exposed electrochemical active sites, higher ion diffusion coefficient, and lower charge-transfer resistance. Herein, a highly opened 3D network of reduced graphene oxide/poly(3,4-ethylenedioxythiophene) (rGO/PEDOT) was constructed through the laser-assisted treatment and in situ vapor phase polymerization methods, which can be employed with gel electrolyte to prepare flexible microsupercapacitors, without conductive additives, polymer binder, separator, or complex processing. These porous open network structures endow the obtained microsupercapacitors with a maximum specific capacitance (35.12 F cm-3 at 80 mA cm-3), the corresponding energy density up to 4.876 mWh cm-3, remarkable cycling stability (with only about 9.8% loss after 4000 cycles), and excellent coulombic efficiency, which are comparable with most previous reported rGO-based microsupercapacitors. Additionally, the microsupercapacitors connected in series/parallel have been conveniently fabricated, followed by being integrated with solar cells as efficient energy harvesting and storage systems. Moreover, the working voltage or energy density of microsupercapacitors array can be easily tailored according to the practical requirements and this work provides a promising approach to prepare high-performance flexible micro-energy device applied in the wearable electronics accordingly.

19.
RSC Adv ; 9(53): 30809-30814, 2019 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-35529378

RESUMEN

A novel electrode material incorporating renewable biomass-derived juglone biomolecules with commercial activated carbon (AC) granules has been through simple ultrasonic dispersion and dissolution-recrystallization and was found to exhibit good electrochemical performance. The juglone biomolecules are prepared by an ultrasound-assisted extraction method from abandoned walnut peel, which decreases pollution and increases economic efficiency. Through the dissolution-recrystallization process with AC, a hierarchical structure with nanosized juglone particles was obtained, and the AC particles worked as scaffolding to strengthen the slight biomolecules, thus expanding the active sites and effectively reducing the dissolution of the active materials. The pseudocapacitance fading mechanism was investigated by ex situ FTIR measurement and the porous structure ensures that the composite electrode has an enhanced specific capacitance of 248 F g-1 compared to 172.8 and 62.5 F g-1 for the respective AC and juglone samples. Besides, the excellent cyclic stability (retained 75% after 3000 charge-discharge cycles) was demonstrated. The highest area-specific capacitance of the composites was 1300 mF cm-2. An asymmetric supercapacitor based on this composite electrode was assembled with an AC electrode as the counter electrode and exhibited good cyclic performance at a voltage of 1.2 V (retained 77% after 3000 charge-discharge cycles), which provides a high energy density of 12 W h kg-1 at a power density of 0.18 kW kg-1 and a high power density of 2 kW kg-1 at an energy density of 9 W h kg-1. This work explores the application of biomolecule-based composites in energy storage devices and provides a potential strategy for constructing environmentally friendly electrodes.

20.
Nanoscale Res Lett ; 13(1): 181, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29904896

RESUMEN

We demonstrate an electrochemical reduction method to reduce graphene oxide (GO) to electrochemically reduced graphene oxide (ERGO) with the assistance of carbon nanotubes (CNTs). The faster and more efficient reduction of GO can be achieved after proper addition of CNTs into GO during the reduction process. This nanotube/nanosheet composite was deposited on electrode as active material for electrochemical energy storage applications. It has been found that the specific capacitance of the composite film was strongly affected by the mass ratio of GO/CNTs and the scanning ratio of cyclic voltammetry. The obtained ERGO/CNT composite electrode exhibited a 279.4 F/g-specific capacitance and showed good cycle rate performance with the evidence that the specific capacitance maintained above 90% after 6000 cycles. The synergistic effect between ERGO and CNTs as well as crossing over of CNTs into ERGO is attributed to the high electrochemical performance of composite electrode.

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