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21.
Ge Zhang Xuewu Ou Chunyu Cui Jianmin Ma Jinghai Yang Yongbing Tang 《Advanced functional materials》2019,29(2)
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
22.
Juan Tao Rongrong Bao Xiandi Wang Yiyao Peng Jing Li Sheng Fu Caofeng Pan Zhong Lin Wang 《Advanced functional materials》2019,29(41)
With the arrival of intelligent terminals, tactile sensors which are capable of sensing various external physical stimuli are considered among the most vital devices for the next generation of smart electronics. To create a self‐powered tactile sensor system that can function sustainably and continuously without an external power source is of crucial significance. An overview of the development in self‐powered tactile sensor array system based on the triboelectric effect is systematically presented. The combination of multi‐functionalization and high performance of tactile sensors aimed at achieving highly comprehensive performance is presented. For the tactile sensor unit, a development is summarized based on the two primary modes which are vertical contact–separation and single‐electrode. For the pressure mapping array, the resolution is significantly enhanced by the novel cross‐type configuration based on the single‐electrode mode. Integrated with other mechanisms, the performance will be further elevated by broadening of the detect range and realizing of visualization of pressure imaging. Then, two main applications of human–machine interaction (HMI) and trajectory monitoring are comprehensively summarized. Finally, the future perspectives of self‐powered tactile sensor system based on triboelectric effect are discussed. 相似文献
23.
This article focuses on an innovative one‐pot fabrication of organic/inorganic hybrid parallepipedic tubes with rectangular cavities displaying multicolor luminescence. Firstly, using a novel back‐to‐back coupled 2,6‐di‐pyrazol‐1‐ylpyridine ligand, blue‐emitting several‐micrometer‐long (ca. 50 μm) parallepipedic organic nanotubes with rectangular cavities were fabricated in THF/water via supramolecular (H‐bonding and π–π stacking) and solvent‐assisted self‐assembly. Secondly, in the same pot, the ligand molecules available on the surface of the ligand nanotubes were reacted with Eu(tta)3 molecules at the solid/liquid interface to form a layer of red‐emitting Eu(III) complex coating on the inner and outer surface of the tubes. The resultant organic/inorganic hybrid parallepipedic nanotubes fabricated using this novel bottom‐up one‐pot technique display tricolor (blue–red–purple) luminescence, i.e., blue and red dual emission from the organic ligand and the Eu(III) complex, respectively, and a purple color due to the mixing of the two colors. This simple technique signifies an innovative and important method in the development of bottom‐up nanotechnology of multiluminescent organic/inorganic hybrid nanotubes. 相似文献
24.
Brenda Long Mary Manning Micheal Burke Bartholomaeus N. Szafranek Giuseppe Visimberga Damien Thompson James C. Greer Ian M. Povey John MacHale Guaylord Lejosne Daniel Neumaier Aidan J. Quinn 《Advanced functional materials》2012,22(4):717-725
A simple, versatile method for non‐covalent functionalization of graphene based on solution‐phase assembly of alkane‐amine layers is presented. Second‐order Møller–Plesset (MP2) perturbation theory on a cluster model (methylamine on pyrene) yields a binding energy of ≈220 meV for the amine–graphene interaction, which is strong enough to enable formation of a stable aminodecane layer at room temperature. Atomistic molecular dynamics simulations on an assembly of 1‐aminodecane molecules indicate that a self‐assembled monolayer can form, with the alkane chains oriented perpendicular to the graphene basal plane. The calculated monolayer height (≈1.7 nm) is in good agreement with atomic force microscopy data acquired for graphene functionalized with 1‐aminodecane, which yield a continuous layer with mean thickness ≈1.7 nm, albeit with some island defects. Raman data also confirm that self‐assembly of alkane‐amines is a non‐covalent process, i.e., it does not perturb the sp2 hybridization of the graphene. Passivation and adsorbate n‐doping of graphene field‐effect devices using 1‐aminodecane, as well as high‐density binding of plasmonic metal nanoparticles and seeded atomic layer deposition of inorganic dielectrics using 1,10‐diaminodecane are also reported. 相似文献
25.
利用绝热扰动法研究了色散缓变光纤中Raman孤子自频移效应,得到了色散缓变光纤中Raman孤子自频移的表达式。结果表明:光纤色散变化率存在一个可以有效抑制孤子自频移的阈值,当光纤色散变化率大于这个阈值时,色散缓变光纤可以抑制孤子自频移,而当光纤色散变化率小于这个阈值时,色散缓变光纤不仅不能抑制孤子自频移,反而加剧孤子自频移。 相似文献
26.
Rolling Friction Enhanced Free‐Standing Triboelectric Nanogenerators and their Applications in Self‐Powered Electrochemical Recovery Systems 下载免费PDF全文
Min‐Hsin Yeh Hengyu Guo Long Lin Zhen Wen Zhaoling Li Chenguo Hu Zhong Lin Wang 《Advanced functional materials》2016,26(7):1054-1062
Heavy metals contained in wastewater are one of the most serious pollutions in natural resources. A self‐powered electrochemical recovery system for collecting Cu ions in wastewater by incorporating a rolling friction enhanced freestanding triboelectric nanogenerator (RF‐TENG) is developed here. The RF‐TENG utilizes integrated cylindrical surfaces using the conjunction of rolling electrification and freestanding electrostatic induction, which shows outstanding output performance and ultrarobust stability. By using the kinetic energy of flowing water, a collection efficiency of up to 80% for Cu2+ ions in wastewater has been achieved. Self‐powered electrochemical systems are one of the most promising applications of TENGs for independent and sustainable driving of electrochemical reactions without the need for any additional power supply. This research is a substantial advancement towards the practical applications of triboelectric nanogenerators and self‐powered electrochemical systems. 相似文献
27.
Polarized Optoelectronics of CsPbX3 (X = Cl,Br, I) Perovskite Nanoplates with Tunable Size and Thickness 下载免费PDF全文
Xuexi Sheng Gaoyu Chen Chong Wang Weiqi Wang Junfeng Hui Qi Zhang Kehan Yu Wei Wei Mingdong Yi Mian Zhang Yu Deng Peng Wang Xiangxing Xu Zhihui Dai Jianchun Bao Xun Wang 《Advanced functional materials》2018,28(19)
Low dimensional semiconductor nanomaterials have shown their tailorable properties for a variety of promising applications in decades. Here a general strategy to synthesize all‐inorganic CsPbX3 (X = Cl, Br, I or their mixture) perovskite 2D nanoplates by introducing additional metal halides MX'2 or MX'3 (M = Cu, Zn, Al or Pb, etc.; X' = Cl, Br or I) is reported. These CsPbX3 perovskite nanoplates have uniform thickness and tunable size, which can be feasibly controlled by the component and ratio of the metal halides, temperature, time, and ligands. The well‐defined morphology of the nanoplates makes them ideal building blocks for the self‐assembly in the face‐to‐face and column‐by‐column arrangement. Compared to the optically isotropic CsPbX3 nanocubes, the 2D CsPbX3 nanoplates exhibit remarkable polarized UV–vis absorption and photoluminescence not only in liquid solvent and solid resin matrix, but also in self‐assembled films. An optoelectronic photodetector sensitive for linear polarized light is fabricated to demonstrate the proof‐of‐concept. 相似文献
28.
29.
使用三维电磁场模拟的方法对相同硅衬底结构下不同布图结构的螺旋电感进行了模拟和分析.通过改变电感匝数、电感金属的宽度和间隔以及电感的内径,模拟和分析了电感性能的变化.给出了引起电感性能变化的原因.结果表明优化电感的几何参数可以有效地改善电感性能.得出了一些实用的设计原则,可有效地指导射频集成电路中集成电感的设计. 相似文献
30.