Dual‐ion batteries (DIBs) have attracted much attention due to their advantages of low cost and especially environmental friendliness. However, the capacities of most DIBs are still unsatisfied (≈100 mAh g?1) ascribed to the limited capacity of anions intercalation for conventional graphite cathode. In this study, 3D porous microcrystalline carbon (3D‐PMC) was designed and synthesized via a self‐templated growth approach, and when used as cathode for a DIB, it allows both intercalation and adsorption of anions. The microcrystalline carbon is beneficial to obtain capacity originated from anions intercalation, and the 3D porous structure with a certain surface area contributes to anions adsorption capacity. With the synergistic effect, this 3D‐PMC is utilized as cathode and tin as anode for a sodium‐based DIB, which has a high capacity of 168.0 mAh g?1 at 0.3 A g?1, among the best values of reported DIBs so far. This cell also exhibits long‐term cycling stability with a capacity retention of ≈70% after 2000 cycles at a high current rate of 1 A g?1. It is believed that this work will provide a strategy to develop high‐performance cathode materials for DIBs. 相似文献
Organic hybrid supercapacitors that consist of a battery electrode and a capacitive electrode show greatly improved energy density, but their power density is generally limited by the poor rate capability of battery‐type electrodes. In addition, flexible organic hybrid supercapacitors are rarely reported. To address the above issues, herein an in‐plane assembled orthorhombic Nb2O5 nanorod film anode with high‐rate Li+ intercalation to develop a flexible Li‐ion hybrid capacitor (LIC) is reported. The binder‐/additive‐free film exhibits excellent rate capability (≈73% capacity retention with the rate increased from 0.5 to 20 C) and good cycling stability (>2500 times). Kinetic analyses reveal that the high rate performance is mainly attributed to the excellent in‐plane assembly of interconnected single‐crystalline Nb2O5 nanorods on the current collector, ensuring fast electron transport, facile Li‐ion migration in the porous film, and greatly reduced ion‐diffusion length. Using such a Nb2O5 film as anode and commercial activated carbon as cathode, a flexible LIC is designed. It delivers both high gravimetric and high volumetric energy/power densities (≈95.55 Wh kg?1/5350.9 W kg?1; 6.7 mW h cm?3/374.63 mW cm?3), surpassing previous typical Li‐intercalation electrode‐based LICs. Furthermore, this LIC device still keeps good electrochemical attributes even under serious bending states (30°–180°). 相似文献
Objective: Innovation in material science has made it possible to fabricate a pharmaceutical material of modifiable characteristics and utility, in delivering therapeutics at a sustained/controlled rate. The objective of this study is to design and optimize the controlled release transdermal films of S-Amlodipine besylate by intercalating hydrophilic and hydrophobic polymers.
Methods: 3(2) factorial design and response surface methodology was utilized to prepare formulations by intercalating the varied concentration of polymers(A) and penetration enhancer(B) in solvent. The effect of these independent factors on drug release and flux was investigated to substantiate the ex-vivo, stability and histological findings of the study.
Results: FTIR, DSC revealed the compatibility of drug with polymers; however, the semicrystallinity in drug was observed under PXRD. SEM micrographs showed homogeneous dispersion and entanglement of drug throughout the matrix. Results from the permeation study suggested the significant effect of factors on the ex vivo permeation of drug. It was observed that drug release was found to be increased with an increase in hydrophilic polymer concentration and PE. The formulations having polymers (EC:PVPK-30) at 7:3 showed maximum drug release with highest flux (102.60?±?1.12?µg/cm2/h) and permeability coefficient (32.78?±?1.38?cm/h). Significant effect of PE on lipid and protein framework of the skin was also observed which is responsible for increased permeation. The optimized formulation was found to be stable and showed no-sign of localized reactions, indicating safety and compatibility with the skin.
Conclusion: Thus, results indicated that the prepared intercalated transdermal matrix can be a promising nonoral carrier to deliver effective amounts of drug. 相似文献
The anodic behaviour of compacted graphite, graphite powder, glassy carbon and reticulated vitreous carbon electrodes in basic sodium chloroaluminate melt in the temperature range 428–573 K was studied using cyclic voltammetry. Chlorine evolution (> + 2.1 V vs Al) alone was the predominant reaction on the compact glassy carbon and fresh RVC electrodes. On compacted graphite, chlorine-assisted chloroaluminate intercalation was found to be a competitive process to the chlorine evolution. At high sweep rates, intercalation/deintercalation near the graphite lattice edges occur faster than chlorine evolution. Subsequent intercalation, however, is a slow process. Chlorine evolution predominates at higher temperatures and at higher anodic potentials. On graphite powders, a more reversible free radical chlorine adsorption/desorption process also occurs in the potential region below chlorine evolution. The process occurs at the grain boundaries, edges and defects of the graphite powder material. Intercalation/deintercalation processes are mainly responsible for the disintegration of graphitic materials in low-temperature chloroaluminate melts. Repeated intercalation/deintercalation cycles result in the irreversible transformation of the electrode surface and electrode characteristics. The surface area of the electrode is increased substantially on cycling. Electrode materials and operating conditions suitable for chlorine generation, intercalation/deintercalation and chlorine adsorption/desorption and power sources based on these processes are identified in this work. 相似文献
First-principles calculations have been performed to study the lithium intercalations in MoS2. The formation energies, changes of volumes, electronic structures and charge densities of the lithium intercalations in MoS2 are presented. Our calculations show that during lithium intercalations in MoS2, the lithium intercalation formation energies per lithium atom are between 2.5 eV to 3.0 eV. The volume expansions of MoS2 due to lithium intercalations are relatively small 相似文献