三元镍基硫属化物纳米棒阵列的简单合成及其高效的电催化析氧性能北大核心CSCD

通过一步溶剂热法成功合成了泡沫镍(NF)支撑的三元镍基硫属化物(Ni_(3)(Se_(x)S_(1−x))_(2))纳米棒阵列。结构表征结果表明,所得三元Ni_(3)(Se_(x)S_(1−x))_(2)纳米棒属于三方物相,在泡沫镍基底上形成了有序的阵列结构。由于其快速的载流子传输效率、丰富的活性位点和多阴离子的协同效应,Ni_(3)(Se_(0.3)S_(0.7))_(2)/NF纳米棒阵列具有最佳的电催化性能。在1.0 mol/L的KOH溶液中,电流密度为50 mA/cm2时,过电势仅为344 mV,塔菲尔斜率为40.17 mV/dec,同时具有优异的电化学稳定性。更重要的是,以商用Pt/C为阴极,Ni_(3)(Se_(0.3)S_(0.7))_(2)/NF纳米棒阵列为阳极进行全分解水实验,仅需要1.49 V的电池电位即可提供10 mA/cm2的电解电流,表现出良好的电解水效果。该研究为电解水技术领域提供了一种高效的电催化剂,也为电化学能源技术中非贵重电催化剂的合理构建提供了有价值的见解。     

Quantitative analysis of human serum leptin using a nanoarray protein chip based on single-molecule sandwich immunoassay

We report a method for the quantitative analysis of human serum leptin, which is a protein hormone associated with obesity, using a nanoarray protein chip based on a single-molecule sandwich immunoassay. The nanoarray patterning of a biotin-probe with a spot diameter of 150 nm on a self-assembled monolayer functionalized by MPTMS on a glass substrate was successfully accomplished using atomic force microscopy (AFM)-based dip-pen nanolithography (DPN). Unlabeled leptin protein molecules in human serum were detected based on the sandwich fluorescence immunoassay by total internal reflection fluorescence microscopy (TIRFM). The linear regression equation for leptin in the range of 100 zM-400 aM was determined to be y = 456.35x + 80,382 (R = 0.9901). The accuracy and sensitivity of the chip assay were clinically validated by comparing the leptin level in adult serum obtained by this method with those measured using the enzyme-linked immunosorbent assay (ELISA) performed with the same leptin standards and serum samples. In contrast to conventional ELISA techniques, the proposed chip methodology exhibited the advantages of ultra-sensitivity, a smaller sample volume and faster analysis time.     

Dual-color prism-type TIRFM system for direct detection of single-biomolecules on nanoarray biochips

This study examined the applicability of a prism-type simultaneous dual-color total internal reflection fluorescence microscopy (TIRFM) system for the simultaneous detection of nano biomolecules on nanoarray biochips at the single-molecule level. The dual-color TIRFM system with two individual laser beams and a high-sensitivity camera was used for the simultaneous dual-color detection of two different nano beads (i.e. 20 nm yellow–green and crimson fluorescent FluoSpheres beads), and single-protein molecules labeled with different fluorescent dyes (i.e. actin from rabbit muscle conjugated with Alexa Fluor^® 488 and Alexa Fluor^® 633 goat anti-rabbit IgG) without a time-delay and the need to move the sample. When this system was applied to two different single-protein molecules labeled with different fluorescent dyes on the GPTS/CHI/GA-modified glass nanoarray chip, the full images of the biomolecules at the single-molecule level were obtained simultaneously in two different colors using a Dual-View™. The dual-color TIRFM system is quite suitable for the biological imaging at the single-molecule level on nanoarray biochips. This study provides a benchmark for directly monitoring the interactions and detecting the colocalization of two different nano biomolecules, and can be applied to the development of a nanoarray biochip at the single-molecule level.     

基于阵列电极的新型混合电容器

混合电容器由于兼具电池高能量密度和超级电容器高功率密度的优势,成为当前储能领域的研究热点。然而,电池电极和电容电极之间容量和功率的不平衡严重限制了混合电容器的实际性能。因此,如何实现二者的有效匹配,优化器件性能是混合电容器实用化的关键。阵列电极的使用打破传统粉末电极中不导电粘结剂对电化学动力学的限制,其独特的结构为正负极的匹配提供了新策略。此专论结合新型储能器件的研究现状以及本课题组在混合电容器方面的探索,简单探讨了混合电容器的储能机理和阵列结构作为电极材料的优势,着重介绍了本课题组近年来在混合电容器领域的研究工作,针对存在的科学问题提出了相应的解决方案,阐明了阵列电极混合电容器在柔性/可穿戴电子器件等领域的应用前景,并展望了混合电容器在未来的发展方向和挑战。     

Fabrication and optical characterization of imaging fiber-based nanoarrays

In this paper, we present a technique for fabricating arrays containing a density at least 90 times higher than previously published. Specifically, we discuss the fabrication of two imaging fiber-based nanoarrays, one with 700 nm features, another with 300 nm features. With arrays containing up to 4.5 × 10⁶ array elements/mm², these nanoarrays have an ultra-high packing density. A straightforward etching protocol is used to create nanowells into which beads can be deposited. These beads comprise the sensing elements of the nanoarray. Deposition of the nanobeads into the nanowells using two techniques is described. The surface characteristics of the etched arrays are examined with atomic force microscopy and scanning electron microscopy. Fluorescence microscopy was used to observe the arrays. The 300 nm array features and the 500 nm center-to-center distance approach the minimum feature sizes viewable using conventional light microscopy.     

Preparation of L-Cys–Au colloid self-assembled nanoarray electrode based on the microporous aluminium anodic oxide film and its application to the measurement of dopamine

A novel method for fabricating a nanoarray electrode combining the template technique with the self-assembled approach was developed. The glassy carbon electrode was modified with the Au nanoarray using micropores of aluminum anodic film as template. Then, the Au nanoarray electrode was self-assembled with L-cysteine (L-Cys) and gold colloid, respectively. In order to evaluate the electrochemical characteristics of L-Cys–Au colloid self-assembled nanoarray electrode, was chosen as molecule probe and cyclic voltammetry was used. In addition, the functional nanoarray electrode was applied to measuring dopamine (DA). The resulting L-Cys–Au colloid self-assembled nanoarray electrode demonstrated that the linear calibration range extended over three orders of magnitude of DA concentrations (1.0 × 10⁻⁹–1.0 × 10⁻⁶ mol/L) and the detection limit was 5.0 × 10⁻¹⁰ mol/L.     

Detection of single-molecule DNA hybridization by using dual-color total internal reflection fluorescence microscopy

We examined the use of prism-type simultaneous dual-color total internal reflection fluorescence microscopy (TIRFM) to probe DNA molecules at the single-molecule level. The system allowed the direct detection of the complementary interactions between single-stranded probe DNA molecules (16-mer) and various lengths of single-stranded target DNA molecules (16-mer and 55-mer) that had been labeled with different fluorescent dyes (Cy3, Cy5, and fluorescein). The polymer-modified glass substrate and the extent of DNA probe immobilization were easily characterized either with standard TIRFM or with atomic force microscopy. However, only dual-color TIRFM could provide unambiguous images of individual single-stranded target DNA molecules hybridized with the correct sequence in the range of fM–aM. Succinic anhydride showed low RMS roughness and was found to be an optimal blocking reagent against non-specific adsorption, with an efficiency of 92%. This study provides a benchmark for directly monitoring the interactions and the detection of co-localization of two different DNA molecules and can be applied to the development of a nanoarray biochip at the single-molecule level.     

Zn基片上ZnO及ZnS/ZnO复合纳米阵列的液相合成及发光性质

采用温和的溶液路线在Zn基片上合成了单晶态的ZnO纳米棒阵列、 纳米片阵列和ZnS/ZnO复合双层纳米棒阵列. 使用X射线粉末衍射仪、 扫描电子显微镜、 高分辨透射电子显微镜、 X射线光电子能谱仪等对产物的组成、 结构及形貌进行了表征. 讨论了表面活性剂在液相合成中对产物形貌的调控作用. 通过室温发射光谱的测定, 研究了所得纳米阵列材料的发光性质.