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101.
Acetate adsorbs onto platinum surfaces under moderate conditions and the presence of acetate on the electrode surface is apparent by voltammetric studies. The adsorption of acetate lends an unusual stability to layers of zinc acetate on the electrode surface. The reduction of an oxidized platinum surface under a zinc acetate coating is sensitive to polar organic molecules in the bulk solution. This sensitivity may provide an avenue to a new class of analytical sensors. 相似文献
102.
Sergej Gamburzev Plamen Atanasov Ebtisam Wilkins 《Sensors and actuators. B, Chemical》1996,30(3):179-183
A potentially implantable glucose biosensor for continuous monitoring of glucose levels in diabetic patients has been developed. The glucose biosensor is based on an amperometric oxygen electrode and glucose oxidase immobilized on carbon powder held in the form of a liquid suspension. The enzyme material can be replaced (the sensor recharged) without sensor disassembly. Diffusion membranes made of silastic coatings over a microporous polycarbonate membrane are used. Calibration curves of the sensors in phosphate buffer solution and in undiluted blood plasma at body temperature have been obtained. The reproducibility of the sensor response in serum at body temperature is demonstrated. The sensors have a stable signal during storage and continuous operation at body temperature for a period of at least one month. 相似文献
103.
采用烧结-机械球磨二步法制备了Mg2Ni(A2B)、Mg1.7Al0.3Ni、Mg2Ni0.8Cr0.2、Mg1.8Al0.2Ni0.8Cr0.2储氢合金材料,采用XRD和SEM研究了A侧取代元素舢和B侧取代元素Cr的加入对Mg2Ni储氢合金组织结构的影响。研究结果表明:Al、Cr元素的同时存在产生了协同改性作用,Cr元素的存在会抑制Al元素与Ni元素之间形成Al3Ni2非吸氢相,能促使Mg、Al、Ni反应形成Mg3AlNi2吸氢相;Al元素的存在会抑制Cr元素与Ni元素形成δ-[Cr,Ni]非吸氢相。 相似文献
104.
Sule Erten-Ela Sadik Cogal Gamze Celik Cogal 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(6):380-384
Poly(3,4-ethylenedioxxythiophene) (PEDOT), polyaniline (PANI) and polythiophene (PTh) based multi-walled carbon nanotube (MWCNT) composites were successfully prepared using RF-rotating plasma grafting method. Morphological characterizations of composites were determined using scanning electron microscopy (SEM), which showed that conducting polymers (CPs) of PEDOT, PANI and PTh were coated on the surface of CNTs. The surface properties of the Carbon Nanotube (CNT) composites were also determined by using Infrared Spectra (FT-IR), X-ray Photon Spectra (XPS), and Scanning Electron Microscopy-Energy Dispersive X-ray Spectra (SEM-EDX) analysis. X-ray photon spectra results confirmed the formation of the composites. Composites of MWCNT were used in dye-sensitized solar cells (DSSCs) as counter electrodes and exhibited short-circuit photocurrent densities of 11.19, 10.70 and 8.54 mA/cm2 for PANI/MWCNT, PTh/MWCNT and PEDOT/CNT, respectively. 相似文献
105.
Graphene has been regarded as a promising candidate for a new generation of transparent electrodes (TEs) due to its prominent characteristics including high optical transmittance, exceptional electronic transport, outstanding mechanical strength, and environmental stability. Comprehensive and critical insights into the latest advances in graphene‐based TEs (GTEs) since, but not limited to 2013, are provided, with an emphasis on fabrication, modification, and versatile applications. Several emerging application areas not previously summarized, including electrochromic devices, supercapacitors, electrochemical and electrochemiluminescent sensors, are discussed in detail. The challenges and prospects in these fields are also addressed. 相似文献
106.
High‐Performance Flexible Transparent Electrode with an Embedded Metal Mesh Fabricated by Cost‐Effective Solution Process
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Arshad Khan Sangeon Lee Taehee Jang Ze Xiong Cuiping Zhang Jinyao Tang L. Jay Guo Wen‐Di Li 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(22):3021-3030
A new structure of flexible transparent electrodes is reported, featuring a metal mesh fully embedded and mechanically anchored in a flexible substrate, and a cost‐effective solution‐based fabrication strategy for this new transparent electrode. The embedded nature of the metal‐mesh electrodes provides a series of advantages, including surface smoothness that is crucial for device fabrication, mechanical stability under high bending stress, strong adhesion to the substrate with excellent flexibility, and favorable resistance against moisture, oxygen, and chemicals. The novel fabrication process replaces vacuum‐based metal deposition with an electrodeposition process and is potentially suitable for high‐throughput, large‐volume, and low‐cost production. In particular, this strategy enables fabrication of a high‐aspect‐ratio (thickness to linewidth) metal mesh, substantially improving conductivity without considerably sacrificing transparency. Various prototype flexible transparent electrodes are demonstrated with transmittance higher than 90% and sheet resistance below 1 ohm sq?1, as well as extremely high figures of merit up to 1.5 × 104, which are among the highest reported values in recent studies. Finally using our embedded metal‐mesh electrode, a flexible transparent thin‐film heater is demonstrated with a low power density requirement, rapid response time, and a low operating voltage. 相似文献
107.
Hydrothermally Oxidized Single‐Walled Carbon Nanotube Networks for High Volumetric Electrochemical Energy Storage
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Tianyuan Liu Amir A. Bakhtiary Davijani Jingying Sun Shuo Chen Satish Kumar Seung Woo Lee 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(25):3423-3431
Improving volumetric energy density is one of the major challenges in nanostructured carbon electrodes for electrochemical energy storage device applications. Herein, a simple hydrothermal oxidation process of single‐walled carbon nanotube (SWNT) networks in dilute nitric acid is reported, enabling simultaneous physical densification and chemical functionalization of the as‐assembled randomly‐packed SWNT films. After the hydrothermal oxidation process, the density of the SWNT films increases from 0.63 to 1.02 g cm?3 and a considerable amount of redox‐active oxygen functional groups are introduced on the surface of the SWNTs. The functionalized SWNT films are used as positive electrodes against Li metal negative electrodes for potential Li‐ion capacitors or Li‐ion battery applications. The functionalized SWNT electrodes deliver high volumetric as well as gravimetric capacities, 154 Ah L?1 and 152 mAh g?1, respectively, owing to the surface redox reactions between the introduced oxygen functional groups and Li ions. In addition, these electrodes exhibit a remarkable rate‐capability by retaining its high capacity of 94 Ah L?1 (92 mAh g?1) at a high discharge rate of 10 A g?1. These results demonstrate the simple hydrothermal oxidation process as an attractive strategy for improving the volumetric performance of nanostructured carbon electrodes. 相似文献
108.
109.
限流BaTiO3陶瓷PTCR元件化学沉积欧姆电极的研究 总被引:1,自引:0,他引:1
本文对程控交换机用过流保护BaTiO3陶瓷PTCR元件不同化学沉积镍和铜电极的耐工频电流冲击性能和稳定性进行了比较研究,对所得结果进行了充分的讨论。 相似文献
110.
Veronika Ostatná 《Electrochimica acta》2008,53(11):4014-4021
In proteomics and biomedicine fast techniques applicable for preliminary tests of the protein properties and structural changes are sought. Methods of electrochemical analysis have been little utilized in these fields. We show that using constant current chronopotentiometric stripping peak H, minute amounts of denatured and reduced bovine serum albumin (BSA) can be easily discriminated from native BSA. Peak H, which is due to catalytic hydrogen evolution, is greatly enhanced in the presence of non-denaturing concentrations of guanidinium chloride. The course of BSA reduction and denaturation can be followed and traces of the damaged protein can be detected in native BSA samples. 相似文献