Au/PATP/PANI膜电极和Au/PATP/PANI/TiO2膜电极的光电化学

聚苯胺（PANI）是一种结构、 性质不同于聚乙炔和聚吡咯的新型导电高聚物,有着十分广泛的应用[1,2].近年来利用光电化学研究聚苯胺的电子结构、 掺杂情况引起人们的重视[3～5].在酸性溶液中电聚合制备聚苯胺的循环伏安曲线上出现两对氧化还原峰,其峰值电位分别为E11/2=0.13 V和E21/2=0.7 V(对饱和甘汞电极).通过改变电极电位,可获得部分氧化态、还原态、氧化态等3种状态的聚苯胺.部分氧化态具有金属导电性,还原态和氧化态均为绝缘体.本文测量3种状态聚苯胺膜电极的光电响应,首次得到其光电流谱,发现聚苯胺一些新的光电化学实验结果.提出了覆盖绝缘体的金属内发射的光电化学模型.同时,在聚苯胺膜上电沉积纳米TiO2微粒膜,得到广谱区的复合光电材料.     

单根聚苯胺纳米线导电性的研究

纳米线(管)的模板合成和导电原子力显微镜(C-AFM)结合是一种近期发展起来研究单根一维纳米结构及阵列导电性的有效方法. 本文利用C-AFM测量了阳极氧化铝(AAO)模板电化学合成制备的单根聚苯胺纳米线的电导率, 研究了直径、氧化还原态对单根聚苯胺纳米线电导率的影响. 从I－V曲线可以看到, 其导电性质与半导体类似，但又不同于半导体． 尚未观察到反向击穿现象，可能原因是, 在一定的反向偏压下的离子脱嵌使得它由部分氧化态（导电态）转变为还原态（绝缘态）；电导率随纳米线直径减小而线性地增加；以ClO₄^－离子掺杂的氧化态和还原态比部分氧化态的电导率低二个数量级.     

聚苯胺纳米点阵列的制备和库仑台阶现象

本文制备了PANI纳米点阵列, 利用导电原子力显微镜(C-AFM)表征了其形貌和导电性能, 在室温下观察到PANI纳米点的库仑台阶(Coulomb staircase)现象, 并利用库仑阻塞效应的理论进行了初步的分析.     

导电聚苯胺的合成、结构、性能和应用

概述了中国科学院长春应用化学研究所对导电聚苯胺合成、结构、性能和应用的研究.从合成可溶性的聚苯胺入手,阐明了聚苯胺的若干基本化学和结构问题,提出并证明了掺杂态聚苯胺的结构模型和掺杂机理;除了质子酸掺杂外,发现了聚苯胺的碘氧化掺杂、光助氧化掺杂和K+注入还原掺杂;开发了分别以环氧树脂和聚氨酯为载体的聚苯胺防腐涂料;运用掺杂剂诱导的溶解性,通过合成带聚乙二醇链的膦酸掺杂剂,实现了导电态聚苯胺的水体系加工.其中的聚苯胺树脂及防腐涂料的生产技术,已经完成中试,正在走向产业化.     

聚苯胺薄膜的离子束效应

本文采用离子注入掺杂技术，研究了全氧化态聚苯胺薄膜的离子束效应．‘４０ｋＶＫ＋离子束注入后，聚苯胺薄膜的电导率随着剂量的增加而迅速增加．当剂量为１×１０１７Ｋ＋／ｃｍ２时，电导率增加了８个数量级．ＦＴＩＲ光谱图显示了Ｋ＋离子注入使全氧化态聚苯胺中的醌亚胺结构发生还原反应．温差电流法测量表明，离子注入区呈现ｎ型半导体特性．四探针法测量了离子注入掺杂聚苯胺的电导率与温度的关系．本文还对离子注入掺杂全氧化态聚苯胺的导电机制进行了初步探讨．     

PANI膜电聚合过程及电控分离苯酚的EQCM研究

通过电沉积方法在镀铂石英晶片上制备了导电聚苯胺(PANI)膜,采用电化学石英晶体微天平(EQCM)技术探讨了苯胺聚合机制及在苯酚溶液中的氧化还原特性.在0.5 mol/L硫酸溶液中结合循环伏安法考察了PANI膜在完全还原态(L)-半氧化态(E)-完全氧化态(P)之间的电活性和稳定性;在不同浓度的苯酚溶液中结合恒电压阶跃...     

氯化铁氧化掺杂的聚苯胺纳米纤维团簇

没有外加质子酸的条件下,以氯化铁为氧化剂和掺杂剂,在界面体系中由苯胺(An)采用“无模板”的方法成功地制备了电导率为10-2～10-1S/cm的聚苯胺纳米纤维(d=20～30nm).实验证明FeCl3同时起到氧化剂和掺杂剂的双重作用,从而进一步简化了导电聚苯胺纳米纤维的合成条件.与使用过硫酸铵为氧化剂的传统聚合方法相比,FeCl3较小的氧化/还原电位使产物具有较小的直径和较高的结晶性.同时发现聚苯胺的形貌和电导率均与[FeCl3]/[An]的比例有关.FTIR,UV-Vis,XRD结构表征证实所得的聚苯胺纳米纤维为掺杂态.     

掺杂/脱掺杂诱导的聚苯胺织物浸润性开关

以三氟乙酸(TFA)作为掺杂剂,三氯化铁为氧化剂,采用原位化学氧化法制得了具有超疏水性能的聚苯胺/棉布复合导电织物(PANI/CCT),所得织物在外界酸度诱导下发生掺杂/脱掺杂反应而导致其由导电态向绝缘态的转变,从而实现超疏水到超亲水的可逆、快速变化.研究结果证实上述的超疏水/超亲水可逆的变化来自聚苯胺与纤维的微/纳米结构和TFA的低表面自由能的协同效应.     

不同铁盐氧化掺杂导电聚苯胺纳米结构的合成及性能研究

在没有外加掺杂剂的条件下,以FeCl3,Fe(NO3)3,Fe2(SO4)3,FePO4等多种铁盐为氧化剂,在水溶液中采用"无模板"的方法制备了具有较高电导率的聚苯胺纳米结构.铁盐是一种强酸弱碱盐,在水溶液中发生水解释放出质子,质子可以作为掺杂剂进入聚苯胺主链,因此,在苯胺的聚合过程中,铁盐同时起到氧化剂和掺杂剂的双重功能,进一步简化了导电聚苯胺纳米结构的合成条件,降低了反应成本.FTIR,UV-Vis,XRD等结构表征证实所得的纳米结构的聚苯胺均为掺杂态.试验发现,铁盐较低的氧化/还原电位使产物具有较小的直径和较高的电导率和结晶性.不同的对阴离子对聚苯胺产物的形貌有一定的影响,但对产物的结构和性能影响不大.铁盐与苯胺单体的比例对聚苯胺的形貌和电导率均有较大的影响.     

高分散铂的巯基化聚苯胺复合物用于甲醇电催化氧化

采用电化学氧化还原方法一步合成聚苯胺/电还原氧化石墨烯(PANI/ERGO),通过电化学辅助2,5-二巯基-1,3,4-噻二唑(DMc T)与聚苯胺(PANI)发生巯基点击反应得到巯基化的聚苯胺/电还原氧化石墨烯(DMcT-PANI/ERGO),以此引进了大量S和N官能团,采用电沉积的方法在巯基化聚苯胺复合物上有效分散铂纳米颗粒(PtNPs)。扫描电镜(SEM)表明铂纳米颗粒能均一高效地分散在巯基化聚苯胺复合物上;循环伏安法(CV)表明PtNPs/DMcT-PANI/ERGO和未经巯基化的复合物材料PtNPs/PANI/ERGO比较,具备较高的电化学活性面积,并且能较好的电催化氧化甲醇。     

Fluorescent Determination of Glucose Using Silicon Nanodots

ABSTRACT

Here is reported a fluorescent biosensor for glucose detection based on water-soluble and pH-responsive silicon nanodots. The silicon nanodots were prepared using a facile hydrothermal method. The advantages of using the silicon nanodots as glucose sensor are twofold. Firstly, the fluorescence of silicon nanodots was quenched by hydrogen peroxide that was produced from glucose oxidation. Secondly, the fluorescence of silicon nanodots was highly sensitive to gluconic acid that was also produced by glucose oxidation. Our results show that this method detected glucose as low as 0.54?µM with a good selectivity and allowed the determination of glucose in serum samples. This method is also simple, rapid, low-toxic and low-cost, thereby hold high application potential for biological assays.     

Study on the Ultrahigh Quantum Yield of Fluorescent P,O‐g‐C3N4 Nanodots and its Application in Cell Imaging

Graphitic carbon nitride nanodots (g‐C₃N₄ nanodots), as a new kind of heavy‐metal‐free quantum dots, have attracted considerable attention because of their unique physical and chemical properties. Although various methods to obtain g‐C₃N₄ nanodots have been reported, it is still a challenge to synthesize g‐C₃N₄ nanodots with ultrahigh fluorescence quantum yield (QY). In this study, highly fluorescent phosphorus/oxygen‐doped graphitic carbon nitride (P,O‐g‐C₃N₄) nanodots were prepared by chemical oxidation and hydrothermal etching of bulk P‐g‐C₃N₄ derived from the pyrolysis of phytic acid and melamine. The as‐prepared P,O‐g‐C₃N₄ nanodots showed strong blue fluorescence and a relatively high QY of up to 90.2 %, which can be ascribed to intrinsic phosphorus/oxygen‐containing groups, and surface‐oxidation‐related fluorescence enhancement. In addition, the P,O‐g‐C₃N₄ nanodots were explored for cell imaging with excellent stability and biocompatibility, which suggest that they have great potential in biological applications.     

Understanding Interactions between Cellular Matrices and Metal Complexes: Methods To Improve Silver Nanodot‐Specific Staining

Metal complexes are frequently used for biological applications due to their special photophysical and chemical characteristics. Due to strong interactions between metals and biomacromolecules, a random staining of cytoplasm or nucleoplasm by the complexes results in a low signal‐to‐background ratio. In this study, we used luminescent silver nanodots as a model to investigate the major driving force for non‐specific staining in cellular matrices. Even though some silver nanodot emitters exhibited excellent specific staining of nucleoli, labeling with nanodots was problematic owing to severe non‐specific staining. Binding between silver and sulfhydryl group of proteins appeared to be the major factor that enforced the silver staining. The oxidation of thiol groups in cells with hexacyanoferrate(III) dramatically weakened the silver‐cell interaction and consequently significantly improved the efficiency of targeted staining.     

微波法制备纳米碳点反应机制与发光机理

为探讨微波法制备纳米碳点发光性质的影响规律与本质,采用微波加热法通过控制微波功率、反应时间以及pH值合成了一系列纳米碳点,并利用荧光激发光谱与发射光谱测试对纳米碳点的发光性质进行了表征,结合紫外吸收光谱与傅立叶红外光谱对反应产物官能团变化分析,最终揭示了微波加热过程中葡萄糖向纳米碳点转变的机制与发光机理。结果表明,采用微波法制备纳米碳点,当微波功率为560 W,反应时间为2.5 min时,获得纳米碳点发光性能最佳。当采用波长370 nm紫外光激发时,对应451 nm的蓝光发射强度最高。伴随纳米碳点溶液pH值从酸性变为碱性,纳米碳点最强发光峰的激发光波长由350 nm显著向高波长方向移动,且发光峰强度显著升高。紫外吸收光谱与傅立叶红外光谱显示反应过程中形成了多环芳香族碳氢化合物,表明微波加热过程中是葡萄糖单糖向多糖聚合并最终发生碳化的过程。不同pH值下纳米碳点发光性质的差异,源于对纳米碳点中C=C键与C=O键比例的调整,从而实现对纳米碳点的光学带隙宽度及激子束缚能等的综合调控。     

基于含有活性铜的碳点电化学传感器选择性检测尿酸

采用水热法制备了含有活性铜的碳点,利用荧光光谱和紫外可见吸收光谱对其光学性质进行了表征.通过电沉积法将其修饰于玻碳电极表面, 构建了电化学生物传感器,采用循环伏安法、交流阻抗法和差分脉冲伏安法对电极的电化学行为进行了考察, 并对其电化学反应机理进行了探讨.结果表明,此传感器对尿酸具有良好的电催化效果,可有效消除抗坏血酸和多巴胺等物质的干扰.在最佳条件下,氧化峰电流与尿酸的浓度在1.00~300 μmol/L范围内呈良好的线性关系, 检出限为0.30 μmol/L(S/N=3).此传感器具有制作简单、选择性好、灵敏度高和线性范围宽等优点,有望应用于实际样品的检测.     

From Metal–Organic Framework to Intrinsically Fluorescent Carbon Nanodots

Highly photoluminescent carbon nanodots (CNDs) were synthesized for the first time from metal–organic framework (MOF, ZIF‐8) nanoparticles. Coupled with fluorescence and non‐toxic characteristics, these carbon nanodots could potentially be used in biosafe color patterning.     

Synthesis,Optical Properties,and Sensing Applications of Gold Nanodots

In this Personal Account, we briefly address our journey in developing photoluminescent nanomaterials for sensing purposes, with a focus on gold nanodots (Au NDs). Their synthetic strategies, optical properties, and sensing applications are emphasized. The Au NDs can be simply prepared from the etching of small‐sized Au nanoparticles (<3 nm in diameter) by thiol compounds such as 11‐mercaptoundecanoic acid under alkaline conditions. This simple approach allows the preparation of various functional Au NDs by choosing different thiol compounds as etching agents. Since the optical properties of Au NDs are highly dependent on the core and shell of each Au ND, the selection of etching reagents is important. Over the years we have developed various sensing systems using Au NDs for the detection of metal ions, anions, and proteins, based on analyte‐induced photoluminescence quenching/enhancement of Au NDs as a result of changes in their oxidation state, shell composition, and structure.     

High quantum yield blue emission from water-soluble Au8 nanodots

Prepared within biocompatible poly(amidoamine) dendrimer hosts, blue emitting Au8 nanodots were prepared with fluorescence quantum yields more than 100 times larger than any previously prepared. The strong size-dependent blue emission from these from monodisperse Au8 nanodots was measured to be 41% in aqueous solution and 52% in methanol. These easily prepared, water-soluble, and high quantum yield gold nanodots lend insight into the molecular nature of small metal nanoclusters and may find application as novel biocompatible fluorophores.     

Developing luminescent silver nanodots for biological applications

Though creation and characterization of water soluble luminescent silver nanodots were achieved only in the past decade, a large variety of emitters in diverse scaffolds have been reported. Photophysical properties approach those of semiconductor quantum dots, but relatively small sizes are retained. Because of these properties, silver nanodots are finding ever-expanding roles as probes and biolabels. In this critical review we revisit the studies on silver nanodots in inert environments and in aqueous solutions. The recent advances detailing their chemical and physical properties of silver nanodots are highlighted with an effort to decipher the relations between their chemical/photophysical properties and their structures. The primary results about their biological applications are discussed here as well, especially relating to their chemical and photophysical behaviours in biological environments (216 references).     

In Situ Immobilization of Palladium Nanodots in C−C Bonded 2D Conjugated Polymers through Suzuki Polymerization at the Liquid–Liquid Interface

Traditional methods for immobilization of noble metal nanodots in 2D materials (2DMs) need multiple steps and unfriendly reaction conditions. Herein, a one-step method was developed by immobilizing in situ palladium nanodots during the preparation of the 2D conjugated polymer (2DCP) through Suzuki polymerization on interface under mild conditions. Through this method, three 2D conjugated nanosheets carrying palladium nanodots were synthesized.