Photoluminescence Blinking and Biexciton Auger Recombination in Single Colloidal Quantum Dots with Sharp and Smooth Core/Shell Interfaces.

There is an inconsistence on whether a smooth core/shell interface can reduce Auger recombination and suppress photoluminescence (PL) blinking in single colloidal quantum dots (QDs). Here, we investigate the influence of a core/shell interface on PL blinking and biexciton Auger recombination by comparing the single-dot PL spectra of CdZnSeS/ZnS core/shell QDs with sharp and smooth interfaces. The inconsistence can be clarified when considering different PL blinking mechanisms.

Developing a Fluorescent Hybrid Nanobiosensor Based on Quantum Dots and Azoreductase Enzyme forMethyl Red Monitoring.

Background: Azo dyes are the most widely used synthetic colorants in the textile, food, pharmaceutical, cosmetic, and other industries, accounting for nearly 70% of all dyestuffs consumed. Recently, much research attention has been paid to efficient monitoring of these hazardous chemicals and their related metabolites because of their potentially harmful effect on environmental issues. In contrast to the complex and expensive instrumental procedures, the detection system based on the quantum dots (QDs) with the superior optochemical properties provides a new era in the pollution sensing and prevention.

Direct Observation of Surface Polarons in Capped CuInS Quantum Dots by Ultrafast Pump-Probe Spectroscopies.

Semiconductor nanocrystals are mostly prepared by colloid chemistry with organic surfactant molecules, and their surface polarization effect on the carrier relaxations are critical to their optoelectronic applications. Until now, the surface polarization effect and detailed photophysical processes of these capped quantum dots (QDs) are still unclear. Here, we studied the dynamics of the photoinduced carriers and capping molecule  vibrations of capped CuInS quantum dots by using the femtosecond pump-probe system in both visible and IR zones.

Highly luminescent red emissive perovskite quantum dots-embedded composite films: ligands capping and caesium doping-controlled crystallization process.

Perovskite quantum dots (PQDs) are emerging as functional luminescence down-shifting materials for light conversion applications. The incorporation of PQDs into a polymeric matrix is a key step to improving their stability, thus facilitating device integration. Compared to the conventional way of mixing the pre-synthesized PQDs into a polymer, the in situ fabrication of perovskite quantum dots-embedded composite films (PQDCFs) is an efficient and cost-effective method, which yields enhanced photoluminescence properties.

NiFe Hydroxide Lattice Tensile Strain: Enhancement of Adsorption of Oxygenated Intermediates for Efficient Water Oxidation Catalysis.

The binding strength of reactive intermediates with catalytically active sites plays a crucial role in governing catalytic performance of electrocatalysts. NiFe hydroxide offers efficient oxygen evolution reaction (OER) catalysis in alkaline electrolyte, however weak binding of oxygenated intermediates on NiFe hydroxide still badly limits its catalytic activity. Now, a facile ball-milling method was developed to enhance binding strength of NiFe hydroxide to oxygenated intermediates via generating tensile strain, which reduced the anti-bonding filling states in the d orbital and thus facilitated oxygenated intermediates adsorption.

Gram-Scale Synthesis of Blue-Emitting CHNHPbBr Quantum Dots Through Phase Transfer Strategy.

Reprecipitation synthesis has been demonstrated to be a simple and convenient route to fabricate high quality perovskite quantum dots toward display applications, whereas the limited chemical yields (< 10%) and difficulty of purification limited its further application. In order to overcome this issue, we here report a modified emulsion synthesis by introducing phase transfer strategy, which achieving effective extraction of newly formed perovskite quantum dots into non-polar solvent and avoiding the degradation of perovskite quantum dots to a large extent. Based on this strategy, gram-scale CHNHPbBr quantum dots were fabricated in 10 mL (~0.

Efficient Light-Emitting Diodes Based on in Situ Fabricated FAPbBr Nanocrystals: The Enhancing Role of the Ligand-Assisted Reprecipitation Process.

In this paper, we reported the in situ fabrication of highly luminescent formamidinium lead bromide (FAPbBr) nanocrystal thin films by dropping toluene as an anti-solvent during the spin-coating with a perovskite precursor solution using 3,3-diphenylpropylamine bromide (DPPA-Br) as a ligand. The resulting films are uniform and composed of 5-20 nm FAPbBr perovskite nanocrystals. By monitoring the solvent mixing of anti-solvent and precursor solution on the substrates, we illustrated the difference between the ligand-assisted reprecipitation (LARP) process and the nanocrystal-pinning (NCP) process.