粉末粒度对AB5型合金电化学性能的影响

研究了粉末粒度对AB5型储氢合金电化学性能的影响.结果表明当合金粉末粒度为22.49～163.8 μm时,随粉末粒度的减小,储氢合金电极的电化学容量降低;由于粉末粒度大的电极负极充放电循环寿命的衰减率小于粉末粒度小的衰减率,所以随粉末粒度的减小,储氢合金电极材料充放电循环寿命缩短.     

AC5型交流阻抗测试系统的建立

本文介绍了作者研制的AC5型电化学交流阻抗测试系统，它的硬件和软件是针对电化学体系而设计的，因而比一般通用型测试系统操作使用方便。AC5型电化学交流阻抗测试系统可用于金属耐蚀性能、缓蚀剂性能和电池等的研究。     

非连续增强铝基复合材料的环境行为

综述了国内外对非连续增强铝基复合材料的环境行为的研究,包括腐蚀形貌和机理、腐蚀电化学、应力腐蚀断裂和氢脆.     

Synthesis and characterization of LiNi0.95-xCoxAl0.05O2 for lithium-ion batteries

Samples of LiNi0.95-xCoxAl0.05O2 （x = 0.10 and 0.15） and LiNiO2, synthesized by the solid-state reaction at 725℃ for 24 h from LiOH-H2O, Ni2O3, Co2O3, and AI（OH）3 under an oxygen stream, were characterized by TG-DTA, XRD, SEM, and electrochemical tests. Simultaneous doping of cobalt and aluminum at the Ni-site in LiNiO2 was tried to improve the cathode performance for lithium-ion batteries. The results showed that co-doping （especially, 5 at.% A1 and 10 at.% Co） definitely had a large beneficial effect in increasing the capacity （186.2 mA.h/g of the first discharge capacity for LiNio.s.42OoaoAlo.0502） and cycling behavior （180.1 mA-h/g after 10 cycles for LiNio.85CooaoAlo.osO2） compared with 180.7 mA.h/g of the first discharge capacity and 157.7 mA.h/g of the tenth discharge capacity for LiNiO2, respectively. Differen- tial capacity versus voltage curves showed that the co-doped LiNio.95_xCoxmlo.osO2 had less intensity of the phase transitions than the pristine LiNiO2.     

基于三维多孔泡沫镍材料的乳糖传感器研究

提出了一种基于三维多孔泡沫镍的乳糖传感器,采用泡沫镍材料作为工作电极,铂电极作为对电极,在0.1 M的NaOH碱性环境中以循环伏安法(CV)和电流-时间曲线法(i-t)建立了乳糖定量检测方法,循环伏安扫描结果证明乳糖可以被泡沫镍氧化,电流-时间检测结果表明乳糖在0.2 mmol/L~3.5 mmol/L的线性浓度范围内,泡沫镍检测乳糖的灵敏度为9.433 1 mA/(cm2·mmol/L),检测限为6.8μmol/L.本文所研究的乳糖传感器具有响应速度快、成本低、高灵敏度、低检测限等优势,具有较好的实际应用价值.     

Rechargeable Aluminum‐Ion Batteries Based on an Open‐Tunnel Framework

Rechargeable batteries based on an abundant metal such as aluminum with a three‐electron transfer per atom are promising for large‐scale electrochemical energy storage. Aluminum can be handled in air, thus offering superior safety, easy fabrication, and low cost. However, the development of Al‐ion batteries has been challenging due to the difficulties in identifying suitable cathode materials. This study presents the use of a highly open framework Mo_{2.5 + y} VO_{9 + z} as a cathode for Al‐ion batteries. The open‐tunnel oxide allows a facile diffusion of the guest species and provides sufficient redox centers to help redistribute the charge within the local host lattice during the multivalent‐ion insertion, thus leading to good rate capability with a specific capacity among the highest reported in the literature for Al‐based batteries. This study also presents the use of Mo_{2.5 + y} VO_{9 + z} as a model host to develop a novel ultrafast technique for chemical insertion of Al ions into host structures. The microwave‐assisted method employing diethylene glycol and aluminum diacetate (Al(OH)(C₂H₃O₂)₂) can be performed in air in as little as 30 min, which is far superior to the traditional chemical insertion techniques involving moisture‐sensitive organometallic reagents. The Al‐inserted Al _x Mo_{2.5 + y} VO_{9 + z} obtained by the microwave‐assisted chemical insertion can be used in Al‐based rechargeable batteries.     

Monitoring the Dynamic Process of Formation of Plasmonic Molecular Junctions during Single Nanoparticle Collisions

The capability to study the dynamic formation of plasmonic molecular junction is of fundamental importance, and it will provide new insights into molecular electronics/plasmonics, single‐entity electrochemistry, and nanooptoelectronics. Here, a facile method to form plasmonic molecular junctions is reported by utilizing single gold nanoparticle (NP) collision events at a highly curved gold nanoelectrode modified with a self‐assembled monolayer. By using time‐resolved electrochemical current measurement and surface‐enhanced Raman scattering spectroscopy, the current changes and the evolution of interfacial chemical bonding are successfully observed in the newly formed molecular tunnel junctions during and after the gold NP “hit‐n‐stay” and “hit‐n‐run” collision events. The results lead to an in‐depth understanding of the single NP motion and the associated molecular level changes during the formation of the plasmonic molecular junctions in a single NP collision event. This method also provides a new platform to study molecular changes at the single molecule level during electron transport in a dynamic molecular tunnel junction.     

Electrochemical Behavior of Single CuO Nanoparticles: Implications for the Assessment of their Environmental Fate

The electrochemical behavior of copper oxide nanoparticles is investigated at both the single particle and at the ensemble level in neutral aqueous solutions through the electrode‐particle collision method and cyclic voltammetry, respectively. The influence of Cl^? and NO₃^? anions on the electrochemical processes occurring at the nanoparticles is further evaluated. The electroactivity of CuO nanoparticles is found to differ between the two types of experiments. At the single‐particle scale, the reduction of the CuO nanoparticles proceeds to a higher extent in the presence of chloride ion than of nitrate ion containing solutions. However, at the multiparticle scale the CuO reduction proceeds to the same extent regardless of the type of anions present in solution. The implications for assessing realistically the environmental fate and therefore the toxicity of metal‐based nanoparticles in general, and copper‐based nanoparticles in particular, are discussed.     

铝合金在盐水环境中腐蚀性能的电化学研究

为了深入研究温度对铝合金材料的腐蚀行为和机理,采用盐水腐蚀方法研究了其在高温条件下的电化学特性及腐蚀机理.选用7A04和5A06铝合金作为研究对象,在质量分数为3.5%的氯化钠溶液中,利用增重法、蔡司显微镜并结合电化学测试方法研究了其在20~80 ℃范围内的腐蚀性能,分析了腐蚀产物的微观形貌,探讨了腐蚀机理.结果表明：两种铝合金试样的腐蚀速率均随温度升高而增大.在Tafel极化曲线图中,对于同一种铝合金,自腐蚀电位随腐蚀温度增加向负方向移动,自腐蚀电流密度和年腐蚀深度随腐蚀温度增加而减小.对同一腐蚀温度下的两种铝合金,5A06铝合金自腐蚀电位低于7A04铝合金,腐蚀电流密度和年腐蚀深度均小于7A04铝合金.电化学阻抗图谱中,两种铝合金在不同条件下的Nyquist图均存在一个容抗弧,极化电阻随腐蚀温度增加而减小.对于同一种铝合金,在3.5%氯化钠溶液中的腐蚀速率会随着温度的升高而增大;在同一腐蚀温度下,5A06铝合金比7A04铝合金更容易发生腐蚀,但腐蚀速率比7A04铝合金慢.     

杂交型DNA电化学生物传感器研究进展

杂交型DNA电化学生物传感器是一类利用核酸互补配对杂交原理检测和分析特定DNA序列的电化学生物传感器。由于其具有快速简便、选择性好、灵敏度高等优点,在临床医学、遗传工程、环境检测、食品安全监测和生物科学等领域有着重要的应用价值。简述了杂交型DNA电化学生物传感器的一般原理,对共价键结合法、自组装法、生物素-亲和索法、电聚合法以及吸附法等单链DNA的固定方法和DNA杂交信号的直接和间接电化学转换机制的近期研究进展进行了深入探讨,并对其在医疗检测和转基因植物检测等基因检测方面的最新应用和发展趋势进行了论述。