Graphene quantum dots/β-cyclodextrin nanocomposites: A novel electrochemical chiral interface for tryptophan isomer recognition

Graphene quantum dots (GQDs) were prepared by pyrolysis of citric acid, and then incorporated into β-cyclodextrin (β-CD) via H-bonds between the oxygen-containing groups on GQDs and the hydroxyl groups on β-CD. The nanocomposites of GQDs and β-CD (GQDs/β-CD) were negatively charged due to the ionization of carboxyl groups of GQDs, and therefore they could be effectively electrodeposited onto a glassy carbon electrode (GCE). The electrodeposited GQDs/β-CD were optically active due to the introduction of β-CDs with well-defined hydrophobic central cavities, and it was employed as an electrochemical chiral interface for enantiorecognition of tryptophan (Trp) isomers.     

Synthesis of enantiomerically pure β,β-diphenylalanine (Dip) and fluorenylglycine (Flg)

A new strategy for the preparation of both enantiomers of two phenylalanine analogues, β,β-diphenylalanine and fluorenylglycine, has been developed. The combination of a high yielding racemic synthesis and a very efficient resolution procedure has provided significant amounts of each amino acid in enantiomerically pure form and suitably protected for use in peptide synthesis. This methodology can be easily applied to the preparation of larger quantities of enantiopure compounds.     

水热法制备Sb2S3纳米棒有序阵列

以Sb(S₂CNEt₂)₃为单源前驱体，通过改变时间、温度、表面活性剂等反应条件，用水热法成功合成了各种尺寸的Sb₂S₃纳米棒及其有序阵列。X-射线衍射(XRD)、能量分散光谱(EDS)以及选区电子衍射(SAED)研究表明纳米棒由正交晶系Sb₂S₃单晶构成。扫描电子显微镜(SEM)和透射电子显微镜(TEM)研究显示Sb₂S     

Development and implementation of a high temperature electrochemical cell for lithium batteries

An electrochemical cell designed to perform high temperature lithium battery tests has been developed adapting a typical Swagelok^® cell. The high temperature cell is intended to work in a wide temperature range, namely from room temperature up to 300 °C. It has been successfully tested at 250 °C using LiFePO₄ as cathode, LiTFSI as molten salt electrolyte and metallic lithium as anode.     

Anti-solvent assisted treatment for improved morphology and efficiency of lead acetate derived perovskite solar cells

An efficient solution-processable route employing Pb(Ac)₂ as lead source and anti-solvent treatment to achieve fully covered and homogenous perovskite films is reported.     

Prospects of electrochemically synthesized hematite photoanodes for photoelectrochemical water splitting: A review

Hematite (α-Fe₂O₃) is found to be one of the most promising photoanode materials used for the application in photoelectrochemical (PEC) water splitting due to its narrow band gap energy of 2.1 eV, which is capable to harness approximately 40% of the incident solar light. This paper reviews the state-of-the-art progress of the electrochemically synthesized pristine hematite photoanodes for PEC water splitting. The fundamental principles and mechanisms of anodic electrodeposition, metal anodization, cathodic electrodeposition and potential cycling/pulsed electrodeposition are elucidated in detail. Besides, the influence of electrodeposition and annealing treatment conditions are systematically reviewed; for examples, electrolyte precursor composition, temperature and pH, electrode substrate, applied potential, deposition time as well as annealing temperature, duration and atmosphere. Furthermore, the surface and interfacial modifications of hematite-based nanostructured photoanodes, including elemental doping, surface treatment and heterojunctions are elaborated and appraised. This review paper is concluded with a summary and some future prospects on the challenges and research direction in this cutting-edge research hotspot. It is anticipated that the present review can act as a guiding blueprint and providing design principles to the scientists and engineers on the advancement of hematite photoanodes in PEC water splitting to resolve the current energy- and environmental-related concerns.     

Manipulation of Organic Afterglow by Thermodynamic and Kinetic Control

The fabrication of room-temperature organic phosphorescence and afterglow materials, as well as the transformation of their photophysical properties, has emerged as an important topic in the research field of luminescent materials. Here, we report the establishment of energy landscapes in dopant-matrix organic afterglow systems where the aggregation states of luminescent dopants can be controlled by doping concentrations in the matrices and the methods of preparing the materials. Through manipulation by thermodynamic and kinetic control, dopant-matrix afterglow materials with different aggregation states and diverse afterglow properties can be obtained. The conversion from metastable aggregation state to thermodynamic stable aggregation state of the dopant-matrix afterglow materials to leads to the emergence of intriguing afterglow transformation behavior triggered by thermal and solvent annealing. The thermodynamically unfavorable reversible afterglow transformation process can also be achieved by coupling the dopant-matrix afterglow system to mechanical forces.     

Copper-and Silver-Mediated Cyanation of Aryl Iodides Using DDQ as Cyanide Source

A new copper and silver‐mediated cyanation of aryl iodides with DDQ as a cyanide source is achieved, providing nitriles with good yields. This new approach represents a safe method leading to aryl nitriles.     

Tribological behaviors of a novel trilayer nanofilm: the influence of outer chain length and interlayer thickness

Polydopamine (coded as PDA) is reported to be very adhesive and reactive due to the attached functional groups, such as amine and hydroxyl groups. In this work, taking advantage of the condensation between Si–OH of the hydroxylated alkyltrichlorosilane (ATS) and C–OH on PDA surface, ATS molecules with different chain carbon number of 10, 14 and 18 were grafted onto the 3‐aminopropyl triethoxysilane (APTES)‐PDA dual‐layer film, which was composed of PDA outerlayer and APTES underlayer, on Si substrate. Thus, hydrophobic trilayer films coded as APTES‐PDA‐ATS were prepared successfully. In order to reveal the dependence of the tribological behaviors upon the microstructures of the film, tribological experiments were conducted on an atomic force microscope and a ball‐on‐plate tribometer. Experimental results showed that the (micro‐) friction reducing (characterized by a parameter of relative friction coefficient or friction coefficient, RFC or FC) and macro‐wear resisting (characterized by anti‐wear life) behaviors were related with the chain length of outerlayer and the PDA thickness. Specifically, on one hand, as the chain length increases, RFC/FC decreased and macro anti‐wear life lengthened; on the other hand, as PDA gets thicker, RFC increased and the anti‐wear life enhanced. Copyright © 2013 John Wiley & Sons, Ltd.