Facile Synthesis of Water-Stable Multicolor Carbonized Polymer Dots from a Single Unconjugated Glucose for Engineering White Light-Emitting Diodes with a High Color Rendering Index

Abstract

Tunable emission carbonized polymer dots (CPDs) are highly desirable for the preparation of optoelectronic devices, especially white light-emitting diodes (WLEDs). In most available studies, polychromatic CPDs are synthesized using aromatic molecules as precursors. However, few studies report the successful synthesis of polychromatic CPDs using two or more unconjugated precursors. In this work, we prepare multicolor fluorescent CPDs from a single unconjugated precursor, glucose, via a hydrothermal reaction. By controlling the particle size and degree of graphitization of the synthesized CPDs, their emission wavelength can be tuned in the range 440–625 nm (i.e., almost the entire visible region). Furthermore, the CPDs can be used to construct LEDs of varying colors, including WLEDs (CIE coordinates: 0.34, 0.36) with the correlated color temperature and color rendering index of 4997 K and 92.69, respectively. In brief, the strategy proposed in this study successfully converts unconjugated glucose into high-performance LEDs with great application potential.

Facile Synthesis of Multi-Emission Nitrogen/Boron Co-Doped Carbon Dots from Lignin for Anti-Counterfeiting Printing

“…The multiple peaks in the mass spectra show an interval of 18n (n is an integer), which agrees well with the relative molecular mass of nH 2 O. This confirms that the conjugated graphene structure is formed in the carbon core by dehydration and condensation of the unconjugated precursor, which is consistent with the conclusions drawn from previous work [ 18 , 26 ].…”

“…The UV-vis spectra of the four NB-CDs all have two main absorption peaks centered at 232 and 281 nm, which correspond to the intrinsic state (π-π*) transition of C=C/C=N. The weak absorption peak located at 344 nm is assigned to the n-π* transition of C=O/C=N [ 26 , 29 ]. The similar absorption behaviors of four NB-CDs imply their similar structures formed via the same synthetic method.…”

“…The absolute QYs of the four CDs excited at 330 and 490 nm increase in the order of CDs-1 < CDs-2 < CDs-4 < CDs-3, while the opposite is true at 300 nm. This may be associated with the difference in the chemical composition of the four NB-CDs [24,26,30]. To determine the surface groups and chemical composition, the FTIR and XPS spectra are characterized.…”

Internal dual-emissive carbon dots for the double-signal detection of procainamide

“…1B, illustrated that the CDs had a graphite-like structure. 23 Additionally, the broad reflection was a consequence of the small size of the Y-CDs. 24…”

Preparation, characterization and cell labelling of strong pH-controlled bicolor fluorescence carbonized polymer dots

“…However, the synthesis of multicolor fluorescence CDs depends on organic precursors (aromatic molecules and solvents), 18 which exhibit potential toxicity and are unsuitable for biological application. Lu et al 19 prepared multicolor CDs through the hydrothermal process of aromatic glucose under acidic conditions, which was used to construct LEDs of varying colors. In addition, owing to the diversity of raw materials, the fluorescence can be tuned by a lot of internal and external factors.…”