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1.
In this work, the SnS2 nanoflowers (SnS2 NFs) were solvothermally prepared in the solvent of ethanol, while SnS2 nanoplates (SnS2 NPs) were obtained through the identical conditions except for the solvent of water. The flowers were assembled with numerous nanosheets with very thin thickness, and the NPs exhibited hexagonal shape. When used as the battery-type electrode material for supercapacitors, the SnS2 NFs delivered a specific capacity of as high as 264.4 C g?1 at 1 A g?1, which was higher than the 201.6 C g?1 of SnS2 NPs. Furthermore, a hybrid supercapacitor (HSC) was assembled with the SnS2 as positive electrode and activated carbon (AC) as negative electrode, respectively. The SnS2 NFs//AC HSC exhibited a high energy density of 28.1 Wh kg?1 at 904.3 W kg?1, which was higher than the 24.2 Wh kg?1 at 844.3 W kg?1 of SnS2 NPs//AC HSC. Especially, when the power density was enhanced to the highest value of 8666.8 W kg?1, the NFs-based device could still hold 20.4 Wh kg?1. In addition, both HSC devices showed an excellent cycling stability after 5000 cycles at 5 A g?1. The present method is simple and can be extended to the preparation of other transition metal sulfides (TMSs)-based electrode materials with brilliant electrochemical performance for supercapacitors.  相似文献   
2.
可穿戴和便携式电子设备迫切需要发展透明超级电容器等电化学储能器件。炭化树叶叶脉由连续的碳纤维网络构成,具有非常好的透明性,且兼具导电性好和质量轻的优点。本文以炭化菩提树叶叶脉网络为集流体,通过溶剂热法在其上原位生长了Ni/Co混合金属-有机框架材料(Ni/Co-MOF)。炭化叶脉的连续碳纤维网络有利于电子连续传输及电解液的输运;Ni/Co-MOF中混合金属中心有利于提供更多的电化学位点存储电荷。所制备的炭化叶脉网络@Ni/Co-MOF透明电极在1mA/cm2电流密度下表现出1.15F/cm2的高面积容量,经过1000次循环后,容量保持率为105.4%,仍具有良好的循环稳定性。以炭化叶脉网络@Ni/Co-MOF和炭化叶脉网络@活性炭组装成非对称透明超级电容器,在1.6V的大电势窗口、1mA/cm2的电流密度下,得到的面积容量为0.47F/cm2、面积能量密度为0.61W·h/cm2;并具有良好的循环稳定性,在循环300圈后,容量保持率为93.6%。炭化叶脉网络@MOF材料的方法将为制备透明功能器件如传感器、光电器件、太阳电池和锂离子电池等应用提供了新途径。  相似文献   
3.
超级电容器中纳米纤维素基电极的研究进展   总被引:2,自引:2,他引:0       下载免费PDF全文
纳米纤维素机械强度高、密度低且表面含有可化学改性的羟基官能团,可作为组装高性能超级电容器电极的优选材料。本文综述了纳米纤维素与导电聚合物、过渡金属氧化物等活性材料制备超级电容器软材料和碳基复合电极的机理,对冷冻干燥、碳化、原位聚合、过滤、涂覆等组装方法进行了详细讨论,并对纳米纤维素基电极的机械性能和电化学性能进行了对比和分析。最后,对纳米纤维素基电极在超级电容器中的应用前景进行了展望。  相似文献   
4.
《Ceramics International》2022,48(15):21317-21326
1T phase molybdenum disulfide (1T-MoS2) has aroused extensive concern in energy storage devices such as supercapacitors due to its large interlayer spacing, high conductivity and good hydrophilicity. However, it is struggle to synthesize 1T-MoS2 with stable 1T phase with high content. Herein, Ammonium ion intercalation molybdenum disulfide (A-MoS2) with high 1T content and stable 3D microsphere structure was successfully synthesized using a facile hydrothermal method. We explained the feasibility of ammonium ion (NH4+) intercalation through density functional theory (DFT) calculations and proved the successful intercalation of NH4+ by XRD and XPS. Through XPS fitting, the 1T phase content is calculated as high as 83.1%. The as-prepared A-MoS2 presents a stable 3D microsphere structure with the interlayer spacing expanded to 0.93 nm, which provides a wide ion diffusion channel that allows ions to pass through quickly. Moreover, the high 1T content increases the hydrophilicity of MoS2, thereby improving the wettability of the electrode, which contributes to the interaction between the electrolyte and electrode. In 1 M Na2SO4, A-MoS2 electrode material displays high specific capacitance of 228 F g?1 at 5 mV s?1 and retains 127 F g?1 at 80 mV s?1, which proves the good rate capability. Furthermore, the assembled α-MnO2//A-MoS2 asymmetric supercapacitor (ASC) displayed a wide operating voltage of 2.1 V. The assembled ASC displays a high energy density of 35.8 Wh?kg?1 at a power density of 525.0 W kg?1, which indicates excellent energy storage performance.  相似文献   
5.
李晓燕  张智慧  姚继明 《纺织学报》2022,43(12):197-202
柔性微型超级电容器作为一种新兴的储能器件,具有充放电速度快、功率密度大、循环寿命长等优点,在可穿戴电子设备领域中具有良好的应用前景。为实现柔性显示器、晶体管、射频识别装置及可穿戴设备等柔性电子产品的协同发展,针对微型超级电容器中存在的关键问题,阐述了制备微型超级电容器的凹版印刷法和丝网印刷方法,认为丝网印刷法工艺简单、耗时短、可集成、易实现工业化生产,该技术制备的叉指结构可在有限平面内实现离子转移;针对导电油墨的核心印刷技术,分析了无机系、有机系及复合型导电油墨研究近况,总结了复合型导电油墨制备的微型超级电容器电容特性,对其应用前景进行展望。  相似文献   
6.
Nafion is suggested as an efficient assistant in preparing supercapacitor by employing nanoparticles. In this work, using a bi-additive of 0.10-mM NaOH + 0.10 g L−1 Nafion, Nafion-assisted electrophoretic co-deposition of Bi2O3–multiwalled carbon nanotubes (MWCNTs) coating is successfully realized in ethanol solvent. The capacitance performances of the electrophoretic coatings in 6.0-M KOH electrolyte are investigated by cyclic voltammetry and galvanostatic charge–discharge techniques. Comparing with Bi2O3 coating prepared with electrophoretic deposition (EPD) by employing other additive (such as polyethyleneimine), the Bi2O3 coating prepared by Nafion-assisted EPD shows a better capacitance performance. Benefiting from the improvement in coating conductivity caused by MWCNTs, with a small additional amount of 4.0 wt.%, the Bi2O3–MWCNTs coating exhibits an amazing 164% increase of mass-specific capacitance (473 F g−1 at the current density of 1.0 A g−1) in comparison with pure Bi2O3 coating (179 F g−1 at the current density of 1.0 A g−1). The cyclic stability test exhibits excellent capacitance retention of 88.7% over 3000 cycles at a constant current density of 10.0 A g−1. This work combines the advantages of MWCNTs, Nafion, and EPD to provide a facile route for preparing Bi2O3-based coating as a high-performance supercapacitor electrode.  相似文献   
7.
《Ceramics International》2021,47(24):34514-34520
In this study, ruthenium was bonded to the reduced graphene oxide in an ultrasonic bath. The aerogel of the mixture was produced at −78 °C. Structural characterization of aerogels was done with XRD and FTIR, surface characterization was performed with STEM, and elemental analysis was conducted by EDX analysis. The produced aerogel composites were transformed into electrodes on conductive Nickel foam. IviumStat, a potentiostat/galvanostat device, was used for the electrochemical characterization of the symmetrical supercapacitors. According to CV voltammograms, rGO/RuO2 aerogels' highest specific capacitance was calculated as 328.6 F g−1 at a potential scan rate of 5 mV s−1. The assembled rGO/RuO2 aerogel-based supercapacitor cell offered a high energy density value of 31.1 W h kg−1 even at the power density of 8.365 kW kg−1; this is comparable to that of lead-acid and nickel-metal hybrid batteries.  相似文献   
8.
为提高纤维状超级电容器的电容性能,将碳纳米管(CNT)纤维进行阳极氧化预处理、金属化处理和电沉积聚苯胺后得到不同的电极材料,分别将CNT、CNT/聚苯胺(CNT-PANI)、CNT/阳极氧化/聚苯胺(CNT-O-PANI)、CNT/阳极氧化/金属化/聚苯胺(CNT-O-Ni-PANI)这4种电极材料组装纤维状超级电容器,并对其结构和电化学性能进行研究。结果表明:经过阳极氧化和金属化处理后,聚苯胺均匀、紧密地分散在碳纳米管纤维表面,并且无团聚、结块等现象;CNT-O-Ni-PANI电极材料制备的超级电容器具有优异的储能性能,其比电容和能量密度远高于其他3种电极材料;在1 A/g的电流密度下,其比电容和能量密度分别为357.8 F/g和178.9 W·h/kg;在10 mV/s的扫速下,其比电容高达1 246.3 F/g;采用CNT-O-Ni-PANI所制备的超级电容器稳定性能较好,在5 A/g的电流密度下,经过10 000次恒流充放电循环后,其电容保持率仍高达99.7%。  相似文献   
9.
This study deals with the utility of mini spray dryer process to improve the dispersibility, of graphene oxide(GO) and its application for high-performance supercapacitor. Initially, the neutral solution of GO was obtained using the modified Hummer's method. After this, the prepared GO solution was processed by mini spray dryer to obtain a more purified, lighter, and dispersed form of GO which is named as spray dryer processed GO (SPGO). The SPGO thus obtained showed excellent dispersibility behavior with various solvents, which is not found in case of conventional oven drying. Furthermore, utility of SPGO and its reduced form (r-SPGO) for supercapacitor applications have been investigated. Results obtained from the cyclic voltammetry(CV) analysis, impedance, and charge-discharge behavior of supercapacitor fabricated using r-SPGO shows enhanced features. Therefore, the simple spray dried GO and its reduced form, that is, r-SPGO can be utilized as a potential candidate for the supercapacitor application. Herein, as synthesized SPGO exhibited the specific capacitance of 12.07 and 37.6 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively, at a scan rate of 5 mV/s. On the other hand, reduced form of SPGO, that is, r-SPGO showed the specific capacitance of 27.16 and 230 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively.  相似文献   
10.
目的 制备高比容量多孔钛/TiO2纳米管三维自支撑一体化复合电极材料。方法 采用非溶剂致相分离法与高温烧结相结合的方法制备出孔径小、空间利用率高的三维多孔钛平板膜,然后经阳极氧化法在其表面生长TiO2纳米管,从而制备出多孔钛/TiO2纳米管复合薄膜电极。结果 以3 μm粒径钛粉为原料,N-甲基-2-吡咯烷酮、聚乙烯吡咯烷酮、聚丙烯腈为添加剂制备钛膜生坯,经刮膜成型后,在氩气保护下经1000 ℃烧结,得到孔径约为2~6 μm的多孔钛平板膜。采用阳极氧化法在多孔钛平板膜上直接生长TiO2纳米管,制得多孔钛/TiO2纳米管复合薄膜电极。该复合薄膜电极在超级电容器中具有良好的电化学性能,其在2 mA/cm2电流密度下,比电容为385.34 mF/cm2,即使电流密度增加到10 mA/cm2,比电容仍能保持在125.14 mF/cm2。结论 相较于TiO2纳米颗粒,采用此方法制备的多孔钛/TiO2纳米管复合薄膜电极具有良好的电化学性能,可为下一代储能器件提供新的思路。  相似文献   
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