Enhanced Photocatalytic Reduction of CO2 to CO through TiO2 Passivation of InP in Ionic Liquids

A robust and reliable method for improving the photocatalytic performance of InP, which is one of the best known materials for solar photoconversion (i.e., solar cells). In this article, we report substantial improvements (up to 18×) in the photocatalytic yields for CO₂ reduction to CO through the surface passivation of InP with TiO₂ deposited by atomic layer deposition (ALD). Here, the main mechanisms of enhancement are the introduction of catalytically active sites and the formation of a pn‐junction. Photoelectrochemical reactions were carried out in a nonaqueous solution consisting of ionic liquid, 1‐ethyl‐3‐methylimidazolium tetrafluoroborate ([EMIM]BF₄), dissolved in acetonitrile, which enables CO₂ reduction with a Faradaic efficiency of 99 % at an underpotential of +0.78 V. While the photocatalytic yield increases with the addition of the TiO₂ layer, a corresponding drop in the photoluminescence intensity indicates the presence of catalytically active sites, which cause an increase in the electron‐hole pair recombination rate. NMR spectra show that the [EMIM]⁺ ions in solution form an intermediate complex with CO₂^?, thus lowering the energy barrier of this reaction.     

Versatile ligands for high-performance liquid chromatography: An overview of ionic liquid-functionalized stationary phases

Ionic liquids (ILs), a class of unique substances composed purely by cation and anions, are renowned for their fascinating physical and chemical properties, such as negligible volatility, high dissolution power, high thermal stability, tunable structure and miscibility. They are enjoying ever-growing applications in a great diversity of disciplines.     

Cu nanoclusters-based ratiometric fluorescence probe for ratiometric and visualization detection of copper ions

Copper is a highly toxic environmental pollutant with bioaccumulative properties. Therefore, sensitive detection of Cu²⁺ is very important to prevent over-ingestion, and visual detection is preferred for practical applications. In this work, we developed a simple and environmental friendly approach to synthesize hyperbranched polyethyleneimine-protected copper nanoclusters (hPEI-Cu NCs) with great stability against extreme pH, high ionic strength, thiols etching and light illumination, which were then conjugated to the surface of silica coated CdSe quantum dots (QDs) to design a ratiometric fluorescence probe. In the presence of different amounts of Cu²⁺ ions, the fluorescence of Cu NCs can be drastically quenched, while the emission from QDs stayed constant to serve as a reference signal and the color of the probe changed from yellow-green to red, resulting in ratiometric and visualization detection of Cu²⁺ ion with high accuracy. The detection limit for Cu²⁺ was estimated to be 8.9 nM, much lower than the allowable level of Cu²⁺ in drinking water (∼20 μM) set by U.S. Environmental Protection Agency. Additionally, this probe can be also applied for the determination of Cu²⁺ ion in complex real water samples.     

Facile Synthesis of the Pentasaccharide Repeating Unit of the Exopolysaccharide from Cryptococcus neoformans Serotype D

β‐D ‐GlcpA‐(1→2)‐[β‐D ‐Xylp‐(1→2)‐α‐D ‐Manp‐(1→3)]‐α‐D ‐Manp‐(1→3)‐α‐D ‐Manp, the repeating unit of the exopolysaccharide from Cryptococcus neoformans serotype D, was synthesized as its 4‐methoxyphenyl glycoside. The approach presented here also provides a route to the synthesis of more complex repeating units of glucuconoxylomannan (GXM) of C. neoformans serotypes A–C.     

Capillary electrophoretic studies on quantum dots and histidine appended peptides self‐assembly

Herein, we designed four peptides appended with different numbers of histidine (His_n‐peptide). We launched a systematic investigation on quantum dots (QDs) and His_n‐peptide self‐assembly in solution using fluorescence coupled CE (CE‐FL). The results indicated that CE‐FL was a powerful method to probe how ligands interaction on the surface of nanoparticles. The self‐assembly of QDs and peptide was determined by the numbers of histidine. We also observed that longer polyhistidine tags (n ≤ 6) could improve the self‐assembly efficiency. Furthermore, the formation and separation of QD‐peptide assembly were also studied by CE‐FL inside a capillary. The total time for the mixing, self‐assembly, separation, and detection was less than 10 min. Our method greatly expands the application of CE‐FL in QDs‐based biolabeling and bioanalysis.     

浓缩钼同位素的纯化新方法及质量分馏测定

基于三氧化钼易升华的特性,建立了一种纯化浓缩钼同位素试剂的新方法.采用天然丰度掺杂样品Synthetic-Mo对纯化过程中的氧化时间、样品加入量及真空蒸发温度等条件进行了优化.用高分辨等离子体质谱分析了样品中杂质的含量,计算得到纯化后95Mo和98Mo浓缩同位素试剂的纯度分别为99.992%和99.990%.通过多接收器等离子体质谱测定纯化前后样品中钼同位素的组成,δX/95Mo(X=92,94,96,97,98,100)值均在仪器测量精度(0.3‰)范围之内,未观察到明显的质量分馏现象.该方法能够满足校正质谱法对浓缩同位素试剂的要求,对建立高准确度的钼同位素丰度比测量方法具有重要意义.