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1.
The synthesis of the tris-cyclometalated iridium(III) complex [Ir(DCP)3] (HDCP = 1-(N,N-diphenyl-amino)-4-(4-chlorophenyl)-phthalazine) from hydrated iridium(III) chloride and the ligand HDCP under mild reaction conditions was described. The photophysical, electrochemical and electrophosphorescent properties of this complex were investigated. Organic light-emitting diodes (OLEDs) using the complex as a dopant and a blend of poly(vinylcarbazole) (PVK) with 2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazol (PBD) as a host exhibited bright red emission at 620 nm with the Commission Internationale de l’Eclairage (CIE) coordinate of (0.67, 0.32). A maximum external quantum efficiency of 13.6% photos/electron with a luminous efficiency of 7.4 cd/A at a current density of 0.73 mA/cm2, and a maximum luminance of 2941 cd/m2 at 99 mA/cm2 were obtained in the device at 4 wt% doping concentration. 相似文献
2.
Volatile Eu complexes, namely Eu(TTA)3Phen, Eu(x)Y(1‐x)(TTA)3 Phen; Eu(x)Tb(1‐x)(TTA)3Phen; Eu, europium; Y, yttrium; Tb, Terbium; TTA, thenoyltrifluoroacetone; and Phen, 1,10 phenanthroline were synthesized by maintaining stichiometric ratio. Various characterization techniques such as X‐ray diffraction (XRD), photoluminescence (PL) and thermo gravimetric analysis/differential thermal analysis (TGA/DTA) were carried out for the synthesized complexes. Diffractograms of all the synthesized complexes showed well‐resolved peaks, which revealed that pure and doped organic Eu3+ complexes were crystalline in nature. Of all the synthesized complexes, Eu0.5 Tb0.5(TTA)3Phen showed maximum peak intensity, while the angle of maximum peak intensity for all complexes was almost the same with slightly different d‐values. A prominent sharp red emission line was observed at 611 nm when excited with light at 370 nm. It was observed that the intensity of red emissions increased for doped europium complexes Eu(x)Y(1‐x)(TTA)3Phen and Eu(x)Tb(1‐x)(TTA)3 Phen, when compared with Eu complexes. Emission intensity increased in the following order: Eu(TTA)3Phen > Eu0.5 Tb0.5(TTA)3Phen > Eu0.4 Tb0.6(TTA)3Phen > Eu0.5Y0.5(TTA)3Phen > Eu0.4Y0.6(TTA)3Phen, proving their potential application in organic light‐emitting diodes (OLEDs). TGA showed that Eu complexes doped in Y3+ and Tb3+ have better thermal stability than pure Eu complex. DTA analysis showed that the melting temperature of Eu(TTA)3 Phen was lower than doped Eu complexes. These measurements infer that all complexes were highly stable and could be used as emissive materials for the fabrication of OLEDs. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
3.
Yttrium is stoichiometrically doped into europium by mole percentage, during the synthesis of Y(1‐x)Eu(x)(TTA)3(Phen), using solution techniques (where x = 0.2, 0.4, 0.5, 0.6 and 0.8, TTA = thenoyltrifluoroacetone and Phen = 1,10‐phenanthroline).These complexes were characterized using different techniques such as X‐ray diffraction, thermogravimetric/differential thermal analysis, optical absorption and emission spectra. Thin films of the doped Eu–Y complexes were prepared on a glass substrate under a high vacuum of 10‐6 Torr. The photoluminescence spectra of these thin films were recorded by exciting the sample at a wavelength of 360 nm. The emission peak for all the synthesized complexes centered at 611 nm; maximum emission intensity was obtained from Y0.6Eu0.4 (TTA)3(Phen). The results proved that these doped complexes are more economical than pure Eu(TTA)3(Phen) and are best suited as red emissive material for energy‐efficient and eco‐friendly organic light‐emitting diodes and displays. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
4.
The crystal structure of the triple‐helical peptide (Pro‐Hyp‐Gly)3‐Pro‐Arg‐Gly‐(Pro‐Hyp‐Gly)4 (POG3‐PRG‐POG4) was determined at 1.45 Å resolution. POG3‐PRG‐POG4 was designed to permit investigation of the side‐chain conformation of the Arg residues in a triple‐helical structure. Because of the alternative structure of one of three Arg residues, four side‐chain conformations were observed in an asymmetric unit. Among them, three adopt a ttg?t conformation and the other adopts a tg?g?t conformation. A statistical analysis of 80 Arg residues in various triple‐helical peptides showed that, unlike those in globular proteins, they preferentially adopt a tt conformation for χ1 and χ2, as observed in POG3‐PRG‐POG4. This conformation permits van der Waals contacts between the side‐chain atoms of Arg and the main‐chain atoms of the adjacent strand in the same molecule. Unlike many other host–guest peptides, in which there is a significant difference between the helical twists in the guest and the host peptides, POG3‐PRG‐POG4 shows a marked difference between the helical twists in the N‐terminal peptide and those in the C‐terminal peptide, separated near the Arg residue. This suggested that the unique side‐chain conformation of the Arg residue affects not only the conformation of the guest peptide, but also the conformation of the peptide away from the Arg residue. © 2014 Wiley Periodicals, Inc. Biopolymers 101: 1000–1009, 2014. 相似文献
5.
Synthesis,photophysics, electrochemistry,thermal stability and electroluminescent performances of a new europium complex with bis(β‐diketone) ligand containing carbazole group
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We synthesized a new europium complex [Eu(ecbpd)3(Phen)] with bis(β‐diketone) ligand containing a carbazole group, in which ecbpd and Phen are dehydro‐3,3′‐(9‐ethyl‐9H‐carbazole‐3,6‐diyl)bis(1‐phenylpropane‐1,3‐dione) and 1,10‐phenanthroline, respectively. Its UV/vis and photoluminescent spectra, quantum yield, luminescence lifetime, electrochemistry, thermal stability and electroluminescent performances were studied. This europium complex showed low efficiency luminescence, which is probably due to the mismatching energy levels of its ligand and Eu3+, as well as the double Eu3+ core resonance. 相似文献
6.
Efficient blue organic light‐emitting diodes using N2,N2,N11,N11,5,6,7,8‐octaphenyltriphenylene‐2,11‐diamine derivatives
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Young Seok Kim Su Jin Jeong Hyun Woo Lee Jwajin Kim Song Eun Lee Young Kwan Kim Seung Soo Yoon 《Luminescence》2016,31(4):1031-1036
In this study, we have synthesized phenyl‐substituted triphenylene derivatives, using the Diels–Alder reaction and the Buchwald–Hartwig reaction. To investigate electroluminescence properties of these materials, multilayer organic light‐emitting diode (OLED) devices were fabricated with a structure of indium–tin–oxide (ITO) (180 nm)/4,4′‐bis(N‐(1‐naphthyl)‐N‐phenylamino)biphenyl (NPB) (50 nm)/blue‐emitting materials (1–3) (30 nm)/bathophenanthroline (Bphen) (35 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm). A device using N2,N2,N11,N11,5,6,7‐heptaphenyltriphenylene‐2,11‐diamine (2) exhibited efficient blue emission with luminous, power, and external quantum efficiencies of 0.92 cd/A, 0.67 lm/W, and 1.17% at 20 mA/cm2, respectively. The Commission International de L'Éclairage coordinates of this device were (x = 0.15, y = 0.09) at 6.0 V. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
7.
Fluorescence enhancement of europium (III) perchlorate by 1,10‐phenanthroline on the 1‐(naphthalen‐2‐yl)‐2‐(phenylsulthio)ethanone complex and luminescence mechanism
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Wen‐Xian Li Xiao‐Dong Xin Shu‐Yan Feng Yu Liu Jing Zhang Bo‐Yang Ao Ying‐Jie Li 《Luminescence》2014,29(7):810-817
A novel ligand, 1‐(naphthalen‐2‐yl)‐2‐(phenylsulthio)ethanone was synthesized using a new method and its two europium (Eu) (III) complexes were synthesized. The compounds were characterized by elemental analysis, coordination titration analysis, molar conductivity, infrared, thermo gravimetric analyzer‐differential scanning calorimetry (TGA‐DSC), 1H NMR and UV spectra. The composition was suggested as EuL5 · (ClO4)3 · 2H2O and EuL4 · phen(ClO4)3 · 2H2O (L = C10H7COCH2SOC6H5). The fluorescence spectra showed that the Eu(III) displayed strong characteristic metal‐centered fluorescence in the solid state. The ternary rare earth complex showed stronger fluorescence intensity than the binary rare earth complex in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 1.49 times as strong as that of the binary system. The phosphorescence spectra were also discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
Fengping Xiao Xuming Yang Hongkang Wang Jun Xu Yulong Liu Denis Y. W. Yu Andrey L. Rogach 《Liver Transplantation》2020,10(23)
Practical applications of room temperature sodium–sulfur batteries are still inhibited by the poor conductivity and slow reaction kinetics of sulfur, and dissolution of intermediate polysulfides in the commonly used electrolytes. To address these issues, starting from a novel 3D Zn‐based metal–organic framework with 2,5‐thiophenedicarboxylic acid and 1,4‐bis(pyrid‐4‐yl) benzene as ligands, a S, N‐doped porous carbon host with 3D tubular holes for sulfur storage is fabricated. In contrast to the commonly used melt‐diffusion method to confine sulfur physically, a vapor‐infiltration method is utilized to achieve sulfur/carbon composite with covalent bonds, which can join electrochemical reaction without low voltage activation. A polydopamine derived N‐doped carbon layer is further coated on the composite to confine the high‐temperature‐induced gas‐phase sulfur inside the host. S and N dopants increase the polarity of the carbon host to restrict diffusion of sulfur, and its 3D porous structure provides a large storage area for sulfur. As a result, the obtained composite shows outstanding electrochemical performance with 467 mAh g?1 (1262 mAh g?1(sulfur)) at 0.1 A g?1, 270 mAh g?1 (730 mAh g?1(sulfur)) after 1000 cycles at 1 A g?1 and 201 mAh g?1 (543 mAh g?1(sulfur)) at 5.0 A g?1. 相似文献
9.
Revealing interaction between sulfobutylether‐β‐cyclodextrin and reserpine by chemiluminescence and site‐directed molecular docking
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The host–guest interaction between sulfobutylether‐β‐cyclodextrin (SBE‐β‐CD) and reserpine (RSP) is described using flow injection‐chemiluminescence (FI‐CL) and site‐directed molecular docking methods. It was found that RSP could inhibit the CL intensity produced by a luminol/SBE‐β‐CD system. The decrease in CL intensity was logarithmic over an RSP concentration range of 0.03 to 700.0 nM, giving a regression equation of ?I = 107.1lgCRES + 186.1 with a detection limit of 10 pM (3σ). The CL assay was successfully applied in the determination of RSP in injection, saliva and urine samples with recoveries in the range 93.5–106.1%. Using the proposed CL model, the binding constant (KCD‐R) and the stoichiometric ratio of SBE‐β‐CD/RSP were calculated to be 7.4 × 106 M‐1 and 1 : 1, respectively. Using molecular docking, it was confirmed that luminol binds to the small cavity of SBE‐β‐CD with a nonpolar interaction, while RSP targeted the larger cavity of SBE‐β‐CD and formed a 1 : 1 complex with hydrogen bonds. The proposed new CL method has the potential to become a powerful tool for revealing the host–guest interaction between CDs and drugs, as well as monitoring drugs with high sensitivity. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
10.
Yelin Hu Aswani Yella Stefan Guldin Marcel Schreier Francesco Stellacci Michael Grätzel Morgan Stefik 《Liver Transplantation》2014,4(14)
Cobalt‐based electrolytes are highly tunable and have pushed the limits of dye‐sensitized solar cells, enabling higher open‐circuit voltages and new record efficiencies. However, the performance of these electrolytes and a range of other electrolytes suffer from slow electron transfer at platinum counter electrodes. High surface area platinum would enhance catalysis, but pure platinum structures are too expensive in practice. Here, a material‐efficient host‐guest architecture is developed that uses an ultrathin layer of platinum deposited upon an electrically conductive scaffold, niobium‐doped tin oxide (NTO). This nanostructured composite enhances the counter electrode performance of dye‐sensitized solar cells (DSCs) using a Co(II/III)BPY3 electrolyte with an increased fill factor and power conversion efficiency (11.26%), compared to analogous flat films. The modular strategy is elaborated by integrating a light scattering layer onto the counter electrode to reflect unabsorbed light back to the photoanode to improve the short‐circuit current density and power conversion efficiency. 相似文献
11.
Daniel Tordera Julien Frey David Vonlanthen Edwin Constable Antonio Pertegás Enrique Ortí Henk J. Bolink Etienne Baranoff M. Khaja Nazeeruddin 《Liver Transplantation》2013,3(10):1338-1343
Electroluminescent devices have the potential to reshape lighting and display technologies by providing low‐energy consuming solutions with great aesthetic features, such as flexibility and transparency. In particular, light‐emitting electrochemical cells (LECs) are among the simplest electroluminescent devices. The device operates with air‐stable materials and the active layer can be resumed to an ionic phosphorescent emitter. As a consequence, LECs can be assembled using solution‐process technologies, which could allow for low‐cost and large‐area lighting applications in the future. High efficiencies have been reported at rather low luminances (<50 cd m?2) and at very low current densities. Moreover, these efficiencies could be sustained for a brief moment only during operation time. Here, we demonstrate that a pulsed driving mode at low current densities leads to unequalled overall performances with excellent efficiencies throughout the lifetime of the device. The lifetime of the LECs is defined as the time it takes to reach 50% of the peak luminance. Upon optimization of various parameters (frequency, duty cycle and average current density), the green LEC reaches efficacies and power efficiencies of 28.2 cd A?1 and 17.1 lm W?1, respectively, at a luminance above 750 cd m?2 and 98 hours lifetime. The present work also rationalizes why high efficiencies have been obtained only at low current densities so far. 相似文献
12.
Enhanced luminescence and white light emission from Eu3+‐co‐doped K3Ca2(SO4)3Cl:Dy3+ phosphor with near visible ultraviolet excitation for white LEDs
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The luminescent properties of europium (Eu)‐ and dysprosium (Dy)‐co‐doped K3Ca2(SO4)3Cl halosulfate phosphors were analyzed. This paper reports the photoluminescence (PL) properties of K3Ca2(SO4)3Cl microphosphor doped with Eu and Dy and synthesized using a cost‐effective wet chemical method. The phosphors were characterized by X‐ray diffraction and scanning electron microscopy. The CIE coordinates were calculated to display the color of the phosphor. PL emission of the prepared samples show peaks at 484 nm (blue), 575 nm (yellow), 594 nm (orange) and 617 nm (red). The emission color of the Eu,Dy‐co‐doped K3Ca2(SO4)3Cl halophosphor depends on the doping concentration and excitation wavelength. The addition of Eu in K3Ca2(SO4)3Cl:Dy greatly enhances the intensity of the blue and yellow peaks, which corresponds to the 4 F9/2 → 6H15/2 and 4 F9/2 → 6H13/2 transitions of Dy3+ ions (under 351 nm excitation). The Eu3+/Dy3+ co‐doping also produces white light emission for 1 mol% of Eu3+, 1 mol% of Dy3+ in the K3Ca2(SO4)3Cl lattice under 396 nm excitation, for which the calculated chromaticity coordinates are (0.35, 0.31). Thus, K3Ca2(SO4)3Cl co‐doped with Eu/Dy is a suitable candidate for NUV based white light‐emitting phosphors technology. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
13.
《Chirality》2017,29(3-4):130-133
Differential scanning calorimetry and nuclear magnetic resonance were used to investigate thermal effects in the guest–host systems where homochiral metal–organic sorbent [Zn2(bdc)(S ‐lac)(dmf)] is considered as a host while 1‐phenylethanol enantiomers and their racemic mixture serve as guest molecules. A maximum energy gain from the guest–host interaction was observed in the system with the racemic mixture. The effect of host–guest recognition was revealed for the case of the host and guest having a similar type of chirality in the presence of antipode guest molecules. 相似文献
14.
Nitrogen‐Doping‐Induced Defects of a Carbon Coating Layer Facilitate Na‐Storage in Electrode Materials
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A nitrogen‐doped, carbon‐coated Na3V2(PO4)3 cathode material is synthesized and the formation of doping type of nitrogen‐doped in carbon coating layer is systemically investigated. Three different carbon‐nitrogen species: pyridinic N, pyrrolic N, and quaternary N are identified. The most important finding is that different carbon‐nitrogen species in the carbon layer have different impacts on the improvement of the electrochemical properties of Na3V2(PO4)3. Pyridinic N and pyrrolic N significantly increase the electronic conductivity and create numerous extrinsic defects and active sites. Quaternary N only increases the electronic conductivity without creating extrinsic defects. Therefore, it is unexpectedly demonstrated that the Na3V2(PO4)3/C+N, in which with minimize content of quaternary N or exist most extrinsic defects, exhibits the best electrochemical performance, particularly the rate performance and cycling stability. For example, when the discharging rate increased from 0.2 C to 5 C, its capacity of 101.9 mAh g?1 decays to 84.3 mAh g?1 and an amazing capacity retention of 83% is achieved. Moreover, even at higher current density of 5 C, an excellent capacity retention of 93% is maintained even after 100 cycles. 相似文献
15.
P. W. Yawalkar S. J. Dhoble N. Thejo Kalyani R. G. Atram N. S. Kokode 《Luminescence》2013,28(1):63-68
The tris(8‐hydroxyquinoline)–aluminium complex is the most important and widely studied as electron transporting and green light emitting material. Alq3 and TbxAl(1‐x)q3 have been synthesized (where x = 0.1, 0.3, 0.5, 0.7 and 0.9) and blended films of Alq3 and TbxAl(1‐x)q3 with PMMA and PS at different percentage weight (wt%) concentrations (e.g., 0.1, 1, 5, 10, 25 and 50 wt%) have been prepared. The synthesized materials and their blended thin films have been characterized by a photoluminescence (PL) technique; the synthesis and PL characterization are reported in this paper. The synthesized metal complex shows bright emission of green light with blue light excitation (440 nm) and the prepared TbxAl(1‐x)q3 phosphor may be applicable in blue chip‐excited OLEDs for the newly developed wallpaper lighting technology. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
16.
We have measured the critical flicker detection frequency (CFDF) and double pulse recognition threshold (DPT) using three LEDs with power peaks at 460, 525 and 625 nm for target illumination. Brightness equalization was performed by customized heterochromatic flicker photometry (cHFP). Reference luminance levels were 170 cd/m2 (blue LED, 60 subjects), 4 cd/m2 (green LED, 20 subjects), and 1 cd/m2 (green LED, 20 subjects). The measurement at 1 cd/m2 was preceded by 15 min of dark adaptation. The angle of view for the target was 3°, and the duration of stimuli was 1 ms. An experimental pulse generator with three channels and a projector was used. No differences in CFDF at different spectral properties of stimulus were observed at all three levels of luminance. Thus, it is concluded that temporal vision resolution does not depend on the spectral properties of visual stimuli. 相似文献
17.
Michael P. Down Emiliano Martínez‐Perin Christopher W. Foster Encarnacin Lorenzo G. C. Smith Craig E. Banks 《Liver Transplantation》2019,9(11)
The first entirely AM/3D‐printed sodium‐ion (full‐cell) battery is reported herein, presenting a paradigm shift in the design and prototyping of energy‐storage architectures. AM/3D‐printing compatible composite materials are developed for the first time, integrating the active materials NaMnO2 and TiO2 within a porous supporting material, before being AM/3D‐printed into a proof‐of‐concept model based upon the basic geometry of commercially existing AA battery designs. The freestanding and completely AM/3D‐fabricated device demonstrates a respectable performance of 84.3 mAh g?1 with a current density of 8.43 mA g?1; note that the structure is typically comprised of 80% thermoplastic, but yet, still works and functions as an energy‐storage platform. The AM/3D‐fabricated device is critically benchmarked against a battery developed using the same active materials, but fabricated via a traditional manufacturing method utilizing an ink‐based/doctor‐bladed methodology, which is found to exhibit a specific capacity of 98.9 mAh m?2 (116.35 mAh g?1). The fabrication of fully AM/3D‐printed energy‐storage architectures compares favorably with traditional approaches, with the former providing a new direction in battery manufacturing. This work represents a paradigm shift in the technological and design considerations in battery and energy‐storage architectures. 相似文献
18.
Flexible Asymmetric Micro‐Supercapacitors Based on Bi2O3 and MnO2 Nanoflowers: Larger Areal Mass Promises Higher Energy Density
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Henghui Xu Xianluo Hu Huiling Yang Yongming Sun Chenchen Hu Yunhui Huang 《Liver Transplantation》2015,5(6)
A flexible asymmetric supercapacitor (ASC) with high energy density is designed and fabricated using flower‐like Bi2O3 and MnO2 grown on carbon nanofiber (CNF) paper as the negative and positive electrodes, respectively. The lightweight (1.6 mg cm?2), porous, conductive, and flexible features make the CNF paper an ideal support for guest active materials, which permit a large areal mass of 9 mg cm?2 for Bi2O3 (≈85 wt% of the entire electrode). Thus, the optimal device with an operation voltage of 1.8 V can deliver a high energy density of 43.4 μWh cm?2 (11.3 W h kg?1, based on the total electrodes) and a maximum power density of 12.9 mW cm?2 (3370 W kg?1). This work provides an example of large areal mass and flexible electrode for ASCs with high areal capacitance and high energy density, holding great promise for future flexible electronic devices. 相似文献
19.
《Liver Transplantation》2018,8(25)
Herein, a novel and effective method to prepare n‐doped MoOx films with highly improved conductivity is reported. The MoOx films are readily prepared by spin‐coating an aqueous solution containing ammonium molybdate tetrahydrate and vitamin C (VC). As confirmed by UV–vis absorption, X‐ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy measurements, Mo(VI) is partially reduced to Mo(V) by VC, resulting in the n‐doping of MoOx. The conductivity of the n‐doped MoOx (H:V‐Mo) film can be enhanced by four orders of magnitude compared to pristine MoOx (H‐Mo), that is, from 1.2 × 10−7 to 1.1 × 10−3 S m−1. The device using a 10 nm H:V‐Mo anode interlayer (AIL) exhibits comparable photovoltaic performance to a poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate)‐modified device. More importantly, the hole transport and collection properties of the H:V‐Mo AILs show outstanding tolerance to thickness variation, that is, with increasing thickness of the H:V‐Mo AIL from 10 to 150 nm, the V oc and fill factor values of the devices remain unchanged. The device based on the blade‐coated H:V‐Mo AIL also has a high power conversion efficiency of 10.6%. To the best of the authors' knowledge, this work demonstrates the first example to prepare metal oxide AILs with outstanding tolerance to thickness, which is promising for the future large‐area manufacturing. 相似文献
20.
Layer‐by‐Layer Na3V2(PO4)3 Embedded in Reduced Graphene Oxide as Superior Rate and Ultralong‐Life Sodium‐Ion Battery Cathode
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Yanan Xu Qiulong Wei Chang Xu Qidong Li Qinyou An Pengfei Zhang Jinzhi Sheng Liang Zhou Liqiang Mai 《Liver Transplantation》2016,6(14)
Na3V2(PO4)3 (NVP) is regarded as a promising cathode for advanced sodium‐ion batteries (SIBs) due to its high theoretical capacity and stable sodium (Na) super ion conductor (NASICON) structure. However, strongly impeded by its low electronic conductivity, the general NVP delivers undesirable rate capacity and fails to meet the demands for quick charge. Herein, a novel and facile synthesis of layer‐by‐layer NVP@reduced graphene oxide (rGO) nanocomposite is presented through modifying the surface charge of NVP gel precursor. The well‐designed layered NVP@rGO with confined NVP nanocrystal in between rGO layers offers high electronic and ionic conductivity as well as stable structure. The NVP@rGO nanocomposite with merely ≈3.0 wt% rGO and 0.5 wt% amorphous carbon, yet exhibits extraordinary electrochemical performance: a high capacity (118 mA h g?1 at 0.5 C attaining the theoretical value), a superior rate capability (73 mA h g?1 at 100 C and even up to 41 mA h g?1 at 200 C), ultralong cyclability (70.0% capacity retention after 15 000 cycles at 50 C), and stable cycling performance and excellent rate capability at both low and high operating temperatures. The proposed method and designed layer‐by‐layer active nanocrystal@rGO strategy provide a new avenue to create nanostructures for advanced energy storage applications. 相似文献