One-pot synthesis of double silane-functionalized carbon dots with tunable emission and excellent coating properties for WLEDs application

One-pot synthesis of nitrogen-doped carbonized polymer dots with tunable emission for multicolor light-emitting diodes

Carbonized polymer dots (CPDs) have highly potential application value in the field of optoelectronic devices due to their preferable stability, excellent optical properties and low cost. Here, the nitrogen-doped carbonized polymer dots (HNCDs) with self-quenching-resistant fluorescence were prepared via a simple solvothermal method with citric acid, urea and 2-hydroxyethyl methacrylate (HEMA) as raw materials. The structure and optical properties of the HNCDs have been explored in detail by various contrast experiments. The results show that HEMA form the poly(HEMA) to modify on the surface of carbonized core, which can overcome the quenching effect of carbonized core. The nitrogen doping is crucial for the red shift emission of solid-state HNCDs. Furthermore, the HNCDs exhibit concentration-dependent emission and excellent compatibility with silicone sol, which lead to their emission red shifted from blue to red with increasing concentration. The HNCDs were further applied to construct the light-emitting diodes (LEDs), and the multicolor LEDs ranging from blue to red can be prepared by simply varying the type of chips and adjusting the concentration of HNCDs in encapsulating material.

Nitrogen and boron co-doped carbon dots as a novel fluorescent probe for fluorogenic sensing of Ce4+ and ratiometric detection of Al3

Carbon dots have been widely focused on the field of metal ion detection due to their excellent optical property. Herein, novel orange fluorescent nitrogen and boron co-doped carbon dots (NB-CDs) are obtained by one-pot solvothermal using p-phenylenediamine and boric acid as raw materials. The NB-CDs exhibit excitation-independent emissions and the maximum emission wavelength is 597 nm at 420 nm excitation. The fluorescence can be quenched by Ce⁴⁺ effectively and selectively, and the detection range of Ce⁴⁺ is gained from 0.14 to 180 μM with a detection limit of as low as 0.14 μM. Furthermore, Al³⁺ can also recombine with NB-CDs surface functional groups, which shows a detection range from 1.07 to 100 μM and a detection limit of as low as 1.07 μM, accompanied with a blue-shift to 527 nm.

Color Conversion Light-Emitting Diodes Based on Carbon Dots: A Review

This paper reviews the state-of-the-art technologies, characterizations, materials (precursors and encapsulants), and challenges concerning multicolor and white light-emitting diodes (LEDs) based on carbon dots (CDs) as color converters. Herein, CDs are exploited to achieve emission in LEDs at wavelengths longer than the pump wavelength. White LEDs are typically obtained by pumping broad band visible-emitting CDs by an UV LED, or yellow-green-emitting CDs by a blue LED. The most important methods used to produce CDs, top-down and bottom-up, are described in detail, together with the process that allows one to embed the synthetized CDs on the surface of the pumping LEDs. Experimental results show that CDs are very promising ecofriendly candidates with the potential to replace phosphors in traditional color conversion LEDs. The future for these devices is bright, but several goals must still be achieved to reach full maturity.