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151.
Dr. Chandan Kumar Karan Sourav Mallick Prof. Dr. C. Retna Raj Prof. Dr. Manish Bhattacharjee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(65):14775-14779
A zinc containing metal–organic gel (Zn-MOG) with embedded free ions, which exhibits self-healing properties, has been synthesized for application in supercapacitors. The activated carbon-based flexible supercapacitor device with the MOG electrolyte has a broad potential window of 2.1 V, with high retention of specific capacitance compared to the traditional polyvinyl alcohol (PVA)-based gel. The Zn-MOG does not require an additional electrolyte. The sodium and sulphate ions embedded in the MOG are sufficient enough for the charge storage. 相似文献
152.
通过对碳纳米管(CNT)膜进行重氮化处理,制备对氯苯胺修饰碳纳米管(pca-CNT)膜,并以pca-CNT膜为基底,原位缩聚生长聚(2,5-二羟基-1,4-苯醌硫)(PDBS),构筑pca-CNT负载PDBS(pca-CNT@PDBS)柔性电极。采用场发射扫描电镜、透射电镜、能谱仪、傅里叶红外光谱和光电子能谱等表征了pca-CNT@PDBS电极材料的形貌和结构,研究了CNT膜功能化之后对电极材料结构及电化学性能的影响。研究表明,当电流密度为1mA/cm^2时,pca-CNT@PDBS柔性电极的比电容达到108.0mF/cm^2,明显高于PDBS电极材料(65.6mF/cm^2)和纯碳纳米管膜负载的PDBS(CNT@PDBS,83.2mF/cm^2)。分别以pca-CNT@PDBS、CNT@PDBS为柔性正极,以CNT膜负载的聚(1,5-二氨基蒽醌)(CNT@PDAA)为柔性负极,与丙烯酸酯橡胶/四乙基四氟硼酸铵-乙腈准固态电解质(ACM/Et4NBF4-AN)匹配组装,得到柔性有机非对称超级电容器。当电流密度为2mA/cm^2时,pca-CNT@PDBS//ACM/Et4NBF4-AN//CNT@PDAA的比电容为79.6mF/cm^2;当功率密度为63.5 mW/cm3时,其能量密度达到1.63 mW·h/cm3。CNT@PDBS//ACM/Et4NBF4-AN//CNT@PDAA在循环7 500次以后,比电容保持率仅为30.5%,而pca-CNT@PDBS//ACM/Et4NBF4-AN//CNT@PDAA循环充放电8 000次后,比电容保持率为80.5%,循环稳定性较前者大幅提高。 相似文献
153.
Yunhe Zhao Prof. Hongxing Dong Dr. Xinyi He Dr. Jing Yu Prof. Rongrong Chen Prof. Qi Liu Prof. Jingyuan Liu Prof. Hongsen Zhang Prof. Jia Yu Prof. Jun Wang 《ChemElectroChem》2019,6(13):3355-3366
Due to the urgent demand for portable electronics, enormous research efforts are devoted for the development of flexible, wearable and lightweight supercapacitors. Herein, we report a cost-effective chemical liquid process followed with a refluxing route to grow CC@CoMoO4-Co(OH)2 nanosheets with Co-based MOF as precursor. The resulting CC@CoMoO4-Co(OH)2-4 electrode delivers a significantly enhanced specific capacitance of 2028 F g−1 at 1 A g−1 and capacitance of 1581.8 F g−1 at 20 A g−1. Furthermore, the flexible all-solid-state asymmetric supercapacitor (CC@CoMoO4-Co(OH)2//AC) is assembled, displays a high energy density of 61 Wh kg−1 at power density of 800 W kg−1, with an excellent cycle stability. These exceptional electrochemical performances could be ascribed to the unique structure and multi-metal ion combination contributes to the ideal synergistic effects, which also signify that the potential application of CC@CoMoO4-Co(OH)2 nansheets in high-performance supercapacitors. 相似文献
154.
Dr. Chao Sun Dr. Jing Zhao Dr. Zhiguang Guo Prof. Yaping Zhao Prof. Zaisheng Cai Prof. Fengyan Ge 《ChemElectroChem》2019,6(15):4049-4058
In this work, we prepared a nitrogen and oxygen co-doped flexible cotton-based carbon electrode with high electrochemical performance by using a simple dyeing and carbonization method for its potential application in wearable energy storage devices. The optimized dyed cotton-based electrode with 10 % o.w.f. (percentage on weigh of fabric) dyeing concentration shows a high areal specific capacitance of 1836±20 mF cm−2 at 2 mA cm−2 in aqueous 6 M KOH, superior cycling lifespan (99.1 % capacitance retention after 5000 cycles), good coulombic efficiency, and high rate property. The outstanding properties can be attributed to the synergistic effect between the double-layer capacitance (superior conductivity, large surface area, and good wetability) and the extra pseudocapacitance originating from N and O heteroatoms in the dye molecules. More importantly, the symmetric supercapacitor created with CDF-10 % electrodes exhibits a significant volumetric specific capacitance of 18.2 F cm−3 and energy density of 5.7 mWh cm−3 at a power density of 45.2 mW cm−3, which can power an electronic clock for several minutes. The impressive resulting performance demonstrates that this inexpensive synthetic method, which can be scaled-up, can be used to create promising materials for wearable electronics. 相似文献
155.
Dr. Bingbing Hu Dr. Chaozhong Guo Dr. Chuanlan Xu Dr. Yuan Cen Jiahong Hu Yan Li Shu Yang Dr. Yuping Liu Prof. Danmei Yu Prof. Changguo Chen 《ChemElectroChem》2019,6(23):5845-5855
Enormous efforts have recently been devoted to exploiting high Faradaic redox active materials with ultrahigh energy density in new generation energy storage systems. In this study, a facile and cost-effective solvothermal method was employed to synthesize high capacitance of rGO in situ encapsulating V2O5 microspheres (note as VrG). Benefiting from its unique hierarchical structure, large number of Faradaic redox active sites, and excellent electronic conductivity of rGO, the VrG composites can provide excellent pseudocapacitive performance with fast charge transfer and reaction kinetics between electrolyte and electrode material. Especially, the post-optimized VrG-5 demonstrates a remarkable discharge specific capacitance of 575 C g−1 at a current density of 1 A g−1 and an outstanding rate capability (48 % capacitance retention with the rate increasing 20 times), which is far better than the precursor component V2O5 under identical conditions. More importantly, the flexible VrG-5//rGO asymmetric supercapacitors device can not only deliver excellent specific capacitance of 237 C g−1 and a high energy density of 46 Wh Kg−1, but also exhibit a superior mechanical flexibility under various bending angles and even 83 % capacitance retention after 5000 cycles under mechanical bending 180°, indicating its great potential application in the future flexible energy storage devices. 相似文献
156.
157.
158.
A stretchable parabolic‐shaped metamaterial (PSM) coated onto polydimethylsiloxane (PDMS) is proposed and demonstrated for operation in the terahertz (THz) frequency range. By stretching the PDMS‐based PSM device along different directions, ultranarrowband, polarization dependent, switchable optical characteristics are obtained. By stretching the PSM width and length in the transverse electric (TE) and transverse magnetic (TM) modes, resonant tuning ranges of 0.55 and 0.32 THz, respectively, are demonstrated for the PSM device. In these deformation ranges, the Q‐factors of the PSM device for different widths and lengths are quite stable and maintained in the range of 9 to 14 for the TE mode, with a high Q‐factor of 50 obtained at resonance for the TM mode. The integration of the PSM on a mechanically deformable PDMS substrate provides potential for use in flexible electronics applications. Furthermore, the PSM device exhibits single‐/dual‐band switching and polarization switching characteristics. These multifunctional states for the PSM device can be determined by mechanical inputs to represent binary digits that can then be used to perform logic operations. Such a stretchable PSM device offers an effective approach for the realization of programmable metamaterials with enhanced optical‐mechanical performance due to its high flexibility, applicability, and cost‐effectiveness. 相似文献
159.
Wei Li Yan‐Qing Li Yang Shen Yue‐Xing Zhang Teng‐Yu Jin Jing‐De Chen Xiao‐Hong Zhang Jian‐Xin Tang 《Advanced Optical Materials》2019,7(21)
Flexible organic light‐emitting diodes (OLEDs) are attracting tremendous attention due to their promise as a key element in bendable display and curved lighting applications. However, their performance in terms of efficiency and bendability is limited, since flexible transparent electrodes with superior electrical, optical, and mechanical properties are rare. Here, a multifunctional electrode architecture that is based on flexible plastic, and consists of electrically conductive silver nanowires, a nanopatterned ZnO outcoupling layer, and a hole‐injection polymer layer, is proposed for the actualization of high‐performance flexible OLEDs. The trapped light in the waveguide and substrate modes is effectively released by integrating aperiodic nanostructures into high‐refractive‐index ZnO layers on both sides of the plastic substrate. A maximum external quantum efficiency of 61.7% and a power efficiency of 126.6 lm W−1 are achieved for the white‐emission flexible OLEDs with broadband and angle‐independent outcoupling enhancement. In addition, the proposed approach allows for high‐level mechanical flexibility, retaining over 80% of the initial efficiency after 3000 cycles of repeated bending. 相似文献
160.
Shuailong Zhang Yifan Zhai Ran Peng Moein Shayegannia Andrew G. Flood Juntian Qu Xinyu Liu Nazir P. Kherani Aaron R. Wheeler 《Advanced Optical Materials》2019,7(20)
Topographical micropatterns (TMPs), or ordered arrays of 3D features on a flat surface, have become important for a wide range of applications. A new optofluidic method based on optoelectronic tweezers to assemble TMPs from suspensions of microparticles in fluid is reported. After assembly, TMPs can be freeze‐dried and then transferred to alternate substrates. 3D simulations are carried out to clarify the experimental results and techniques are developed to evaluate pattern‐transfer fidelity, which is found to be >90% for a wide range of different structures. The optofluidic assembly method described here is facile and accessible, suggesting utility for a wide range of microfabrication and microassembly applications in the future. 相似文献