Concentration dependent carbon nanodots: Tunable luminescent color and fluorescence excitation-wavelength dependence.

Carbon nanodots (CNDs) exhibiting concentration dependent properties have been synthesized through a one-pot hydrothermal reaction process utilizing diethylenetriamine and l-aspartic acid. At solid-state or high concentrations, the CNDs display excitation-wavelength independent fluorescence (FL) emissions, while at low concentrations, they exhibit excitation-wavelength dependent FL emissions. Detailed characterization of the structure and optical properties reveals that the concentration dependent FL properties can be ascribed to the intrinsic-state luminescence of the CNDs at low concentrations and the assembled-state luminescence at solid-state/high concentrations.

Crystalline-Amorphous Interface Coupling of NiS/NiP/NF with Enhanced Activity and Stability for Electrocatalytic Oxygen Evolution.

The rational design of highly efficient and stable electrocatalysts for the oxygen evolution reaction (OER) is an urgent need but remains challenging for various sustainable energy systems. How to adjust the atomic structure and electronic structure of the active center is a key bottleneck problem. Accelerating the electron transfer process and the deep self-reconstruction of active sites could be a cost-effective strategy toward electrocatalytic OER catalyst development.

Searching for the true origin of the red fluorescence of leaf-derived carbon dots.

We report for the first time that the red fluorescence of leaf-derived carbon dots is derived from chlorophyll, and a possible formation structure is proposed. By controlling the solvothermal reaction temperature, the new luminescence center of CDs can be adjusted. This work provides unprecedented insights into the luminescence mechanism of biomass-derived CDs.

Influence of Nitrogen-Doped Carbon Quantum Dots on the Electrocatalytic Performance of the CoP Nanoflower Catalyst for OER.

Cobalt phosphides modified by nitrogen-doped carbon quantum dots (CoP-NCQDs) were successfully constructed by a facile and low-cost hydrothermal treatment, which is expected to replace traditional noble-metal oxygen evolution reaction electrode materials. Detailed experiments and findings show that nitrogen-doped carbon quantum dots (NCQDs) have a significant impact on the morphology of the CoP catalyst, and nitrogen doping can regulate the surface-active sites to obtain the catalyst with abundant structural defects. Simultaneously, nitrogen doping can regulate the content of pyridinic N and pyrrolic N, which exerts positive effects on the formation of the bond structure and electron conduction between NCQDs and CoP.

Simple Strategy for Scalable Preparation Carbon Dots: RTP, Time-Dependent Fluorescence, and NIR Behaviors.

Transforming carbon dots (CDs) fluorescent materials into smart materials with complex functions is a topic of great interest to nanoscience. However, designing CDs with regulating fluorescence/phosphorescence that can be visually monitored with the environment changes in real-time remains a challenge. Here, a very simple strategy, one-step solvent-free catalytic assistant strategy, which is low cost, facile, environment-friendly, and high throughput, is put forward.

β-Pyridylenolate zinc catalysts for the ring-opening homo- and copolymerization of ε-caprolactone and lactides.

A family of zinc β-pyridylenolates with varying α,β-substituents has been synthesized. A direct reaction of β-pyridyl ketone ligands with ZnEt in toluene afforded dimeric [LZnEt] (L = (2-CHN)-C(R)[double bond, length as m-dash]C(R)-O-). X-ray structural data revealed that all the [LZnEt] complexes exist as μ-O-bridged dimers in the solid state, although they adopt a different geometry.