Networking State of Ytterbium Ions Probing the Origin of Luminescence Quenching and Activation in Nanocrystals.

At the organic-inorganic interface of nanocrystals, electron-phonon coupling plays an important but intricate role in determining the diverse properties of nanomaterials. Here, it is reported that highly doping of Yb ions within the nanocrystal host can form an energy-migration network. The networking state Yb shows both distinct Stark splitting peak ratios and lifetime dynamics, which allows quantitative investigations of quenching and thermal activation of luminescence, as the high-dimensional spectroscopy signatures can be correlated to the attaching and de-attaching status of surface molecules.

Optimized Metal Chalcogenides for Boosting Water Splitting.

Electrocatalytic water splitting (2HO → 2H + O) is a very promising avenue to effectively and environmentally friendly produce highly pure hydrogen (H) and oxygen (O) at a large scale. Different materials have been developed to enhance the efficiency for water splitting. Among them, chalcogenides with unique atomic arrangement and high electronic transport show interesting catalytic properties in various electrochemical reactions, such as the hydrogen evolution reaction, oxygen evolution reaction, and overall water splitting, while the control of their morphology and structure is of vital importance to their catalytic performance.

Large Band Gap Narrowing and Prolonged Carrier Lifetime of (CHNH)PbI under High Pressure.

Due to their superior optical and electronic properties and good stability, 2D organic-inorganic halide perovskites (OIHPs) exhibit strong potential for optoelectronic applications. However, the large band gap, short carrier lifetime, and high resistance hinder their practical performance. In this work, the band gap is successfully tuned, the carrier lifetime is prolonged, and the resistance of (CHNH)PbI (BAPbI) is reduced directly using high pressure.

Perfection of Perovskite Grain Boundary Passivation by Eu-Porphyrin Complex for Overall-Stable Perovskite Solar Cells.

The formation of defects at surfaces and grain boundaries (GBs) during the fabrication of solution-processed perovskite film are thought to be responsible for its instability. Herein, Eu-porphyrin complex (Eu-pyP) is directly doped into methylammonium lead triiodide (MAPbI) precursor, perfectly fabricating 2D (Eu-pyP)MA Pb I platelets inlaying the GBs of 3D polycrystalline interstices in this protocol. The device based on Eu-pyP doped perovskite film possesses a champion efficiency of 18.

A quadruple cascade protocol for the one-pot synthesis of fully-substituted hexahydroisoindolinones from simple substrates.

A new and efficient synthetic method to obtain fully-substituted hexahydroisoindolinones was developed by using bifunctional tertiary amine-thioureas as powerful catalysts. As far as we know, there is no efficient synthetic method developed toward fully-substituted hexahydroisoindolinones. The products were obtained in good yield and diastereoselectivity.

A general solid-state synthesis of chemically-doped fluorescent graphene quantum dots for bioimaging and optoelectronic applications.

Graphene quantum dots (GQDs) have attracted increasing interest because of their excellent properties such as strong photoluminescence, excellent biocompatibility and low cost. Herein, we develop a general method for the synthesis of doped and undoped GQDs, which relies on direct carbonization of organic precursors in the solid state.

Synthesis, thermodynamics stability constant and relaxation properties of neutral Gd(III) complex with derivative from diethylene triamine pentaacetic acid and p-hydroxybenzoyl hydrazine.

A novel ligand, diethylenetriamine-N,N''-bis(acetyl-p-hydroxybenzoyl hydrazine)-N,N',N''-triacetic acid (H3L) was synthesized and characterized on the basis of elemental analysis, molar conductivity, 1H-NMR spectrum, FAB-MS, TG-DTA analysis and IR spectrum. Its complex of Gd(III) holding promise of magnetic resonance imaging (MRI) was synthesized, and relaxivity (R1) of complex and Gd(DTPA)2- used as a control was determined in water solution, respectively. The relaxivity of GdL (R1 = 6.