亚微米电喷雾喷针在非变性质谱分析中的研究进展

非变性质谱技术已成为表征蛋白质结构的重要工具之一。与传统的电喷雾喷针(Electrospray emitter,ESI emitter)相比,亚微米电喷雾喷针具有改变离子电荷态分布和降低盐离子加合等多种特性,可在生理环境下直接解析蛋白质的结构。该文综述了亚微米电喷雾喷针的特性及其在非变性质谱分析中的应用,并对其未来的发展趋势进行了展望。     

中性或弱酸性体系下锌基水系电池负极材料研究进展

锌具有原料丰富、质量轻便、金属导电性与延展性好以及理论比容量高等优势,可以作为绿色可充电电池的理想电极材料。其中,以中性或弱酸性水溶液为电解质、锌为负极的锌基水系电池具有安全性高、电池材料廉价无毒、制备工艺简单、环境友好等特点,在储能和动力电池领域具有极高的应用价值和发展前景。但电池充放电过程中伴随的锌枝晶、析氢、腐蚀、钝化等问题限制了其实际应用。本文综述了锌基水系电池负极存在的问题及当前的解决策略,并对其负极研究发展方向进行了展望。     

基于多肽识别的电化学生物传感技术

多肽具有分子量小、易于合成、生物兼容性好、稳定性高及序列灵活多样等优点。因此,多肽作为新型生物识别元件,已被广泛应用于生物传感器的构建。电化学分析灵敏度高、准确度好、设备简单、检测范围广且易于操作。本文介绍了基于多肽识别的电化学生物传感器技术,包括多肽的修饰与固定化、多肽与待测物的识别及检测原理;综述了近五年多肽电化学生物传感器对重金属离子、小分子、蛋白质、细菌和病毒的检测;展望了肽基电化学生物传感器的发展趋势。     

Carbazole‐based colorimetric and fluorescent probe for Cu2+ and its utility in bio‐imaging and real water samples

A new carbazole functionalized Schiff base CBM was synthesized and characterized. CBM can selectively recognize Cu²⁺ via UV–vis and fluorescence signal among common biologically relevant metal ions. When Cu²⁺ was added to CBM, there was a significant enhancement at the maximum absorption wavelength of 393 nm and with a distinct blue shift. The maximum emission peak was significantly attenuated by a factor of about 15 times at 535 nm and the blue shift of emission wavelength was observed. When other metal ions were added, there was no remarkable change at the maximum absorption and emission peak. Under the illumination of 365 nm ultraviolet lamp, the color of the CBM solution changed from light blue to dark blue after the addition of Cu²⁺. The combination mechanism of CBM with Cu²⁺ was nicely explored by density functional theory studies. The probe CBM has good cell permeability, fluorescence electron microscopy experiments show that CBM can be used as a fluorescent probe to detect the presence or absence of Cu²⁺ in Hela cells. Furthermore, the probe CBM can also be used for the detection of copper ions in actual water samples.     

Electrochemical aptamer sensor for highly sensitive detection of mercury ion with Au/Pt@carbon nanofiber‐modified electrode

In this paper, an electrochemical aptamer sensor was proposed for the highly sensitive detection of mercury ion (Hg²⁺). Carbon nanofiber (CNF) was prepared by electrospinning and high‐temperature carbonization, which was used for the loading of platinum nanoparticles (PtNPs) by the hydrothermal method. The Pt@CNF nanocomposite was modified on the surface of carbon ionic liquid electrode (CILE) to obtain Pt@CNF/CILE, which was further decorated by gold nanoparticles (AuNPs) through electrodeposition to get Au/Pt@CNF/CILE. Self‐assembling of the thiol‐based aptamer was further realized by the formation of Au‐S bond to get an electrochemical aptamer sensor (Aptamer/Au/Pt@CNF/CILE). Due to the specific binding of aptamer probe to Hg²⁺ with the formation of T‐Hg²⁺‐T structure, a highly sensitive quantitative detection of Hg²⁺ could be achieved by recording the changes of current signal after reacting with Hg²⁺ within the concentration range from 1.0 × 10^?15 mol/L to 1.0 × 10^?6 mol/L and the detection limit of 3.33 × 10^?16 mol/L (3σ). Real water samples were successfully analyzed by this method.     

含异原子石墨炔基电极材料的研究进展

碳材料具有价格低廉、 易制备、 环境友好、 导电性高、 比表面积大以及适合离子存储和迁移等优点, 已成为目前应用于电化学储能器件电极的重要材料之一. 石墨炔(GDY)是一种新型的二维碳同素异形体, 由sp²碳杂化形式的苯环和sp碳杂化形式的炔键构成. 这种独特的化学结构一方面保持了碳材料良好的导电特性, 另一方面形成了新颖的离子传输通道, 为碳材料带来了不同的离子传输和存储特性. 与此同时, 由于石墨炔的空间结构可调性, 可以通过引入异原子微调石墨炔电子结构, 拓展石墨炔在电极材料领域的应用. 本文重点对近几年异原子杂化石墨炔基电极材料在锂离子电池、 钠离子电池、 金属硫电池、 电容器、 金属空气电池和电极保护等储能领域的研究工作进行总结, 并对未来石墨炔类材料在储能领域的发展进行了展望.     

二次离子电池高比容量负极碳载体的研究进展

二次离子电池商业化负极石墨的比容量已接近理论比容量. 合金型负极和金属负极因具有高比容量而受到广泛关注, 但其循环性能差和安全性问题限制了实际应用, 据此提出载体设计策略. 碳材料具有来源广泛、 易于调控等特性, 常用作二次离子电池高比容量负极的载体. 本文从碳载体的孔结构、 比表面积、 电子导电率、 离子导电率、 杂原子掺杂和界面修饰的角度出发, 综述了其在硅基、 磷基、 锗基、 锡基负极以及金属锂、 钠等负极中的研究进展, 展望了碳载体的发展前景和方向.     

锂离子电池硅氧化物负极首次库伦效率的影响因素与提升策略

硅氧化物(SiO_x, 0<x≤2)具有高的比容量和低的嵌锂电位, 且体积膨胀率显著低于纯硅负极, 因而被认为是替代传统石墨负极材料的理想选择之一. 然而SiO_x负极在首次嵌锂过程中表面形成的固体电解质界面膜(SEI)以及大量的不可逆产物, 造成其首次库伦效率偏低, 严重阻碍了SiO_x负极的实际应用. 本文从SiO_x的结构模型出发, 系统阐述了SiO_x负极的嵌锂机理以及首次库伦效率低的原因; 归纳了SiO_x负极首次库伦效率的提升策略及其研究进展; 并对提升SiO_x负极首次库伦效率的未来发展方向进行了展望.     

固相烧结法制备锂离子电池正极材料Li2FeP2O7及其电化学性能研究

介绍了一种先冷冻干燥后固相烧结制备正极材料Li₂FeP₂O₇的方法. 利用X射线衍射(XRD)、 扫描电子显微镜(SEM)、 透射电子显微镜(TEM)和傅里叶变换红外光谱(FTIR)对材料的组成和形态进行表征, 并通过循环伏安曲线(CV)和电化学阻抗谱(EIS)研究了Li₂FeP₂O₇材料的电化学性能. 研究发现, 合成Li₂FeP₂O₇的最佳温度为590 ℃, 此温度下反应较完全且产物杂质较少, 1.6C倍率下的放电比容量达到55 mA·h·g^?1, 明显高于其它温度下合成样品的放电比容量. 该温度下合成的Li₂FeP₂O₇还具有低阻抗和较大的交换电流密度, 说明这种合成方式有利于提高锂离子在Li₂FeP₂O₇中的扩散.     

Design and Construction of 3D Porous Na3V2(PO4)3/C as High Performance Cathode for Sodium Ion Batteries

An easy and delicate approach using cheap carbon source as conductive materials to construct 3D sequential porous structural Na3V2(PO4)3/C(NVP/C)with high performance for cathode materials of sodium ion battery is highly desired.In this paper,the NVP/C with 3D sequential porous structure is constructed by a delicate approach named as“cooking porridge”including evaporation and calcination stages.Especially,during evaporation,the viscosity of NVP/C precursor is optimized by controlling the adding quantity of citric acid,thus leading to a 3D sequential porous structure with a high specific surface area.Furthermore,the NVP/C with a 3D sequential porous structure enables the electrolyte to interior easily,providing more active sites for redox reaction and shortening the diffusion path of electron and sodium ion.Therefore,benefited from its unique structure,as cathode material of sodium ion batteries,the 3D sequential porous structural NVP/C exhibits high specific capacities(115.7,88.9 and 74.4 mA·h/g at current rates of 1,20 and 50 C,respectively)and excellent cycling stability(107.5 and 80.4 mA·h/g are remained at a current density of 1 C after 500 cycles and at a current density of 20 C after 2200 cycles,respectively).