Deep-Ultraviolet Emissive Carbon Nanodots

Abstract

Deep-ultraviolet (DUV) emissive carbon nanodots (CNDs) have been designed theoretically and demonstrated experimentally based on the results of first-principles calculations using the density functional theory method. The emission of the CNDs is located in the range from 280 to 300 nm, which coincides well with the results of theoretical calculation results. The photoluminescence (PL) quantum yield (QY) of the CNDs is up to 31.6%, and the strong emission of the CNDs originates from core-state (π−π*) carriers' radiative recombination and surface passivation. Benefiting from the core-state emission and surface group passivation, the emission of the CNDs is independent of the excitation wavelength and ambient solvent. DUV light-emitting diodes (LEDs) have been fabricated based on the DUV emissive CNDs, and the LEDs can be used as the excitation source to excite blue, green, and red CNDs, indicating their potential application in DUV light sources. This work may provide a clue for the designing and realizing of DUV emissive CNDs, thus promising the potential application of CNDs in DUV light-emitting sources.

Ultra‐Bright and Stable Pure Blue Light‐Emitting Diode from O, N Co‐Doped Carbon Dots

“…[ 30 ] The absence of toxic elements is one of the greatest advantages for large‐scale applications in devices. [ 31 ] However, pure blue CDs‐LEDs are still an urgent challenge for full spectrum CDs based LEDs.…”

Lifetime‐Engineered Carbon Nanodots for Time Division Duplexing

“…Carbon nanodots (CNDs), as recently emerging luminescent nanoparticles, have been widely applied in light‐emitting diodes, [ 15–18 ] cell imaging, [ 19–22 ] information encryption, [ 23–31 ] and biosensing [ 32–35 ] because of their excellent optical performance, environment‐friendliness, and high stability. [ 36–38 ] Considering capacious luminescent lifetime domain and eco‐friendly performance of CNDs, they are ideal candidates for optical multiplexing. Yang et al.…”

Progress in Carbon Dots from the Perspective of Quantum Dots

“…(c) 碳点的尺寸 依赖发光性质的实验及理论计算结果 [20] . (d) 碳点的表面依赖发光性 质 [126] 对于传统量子点, 通常使用光致发光, 不严格区分 荧光和磷光发射; 而碳点中发现了这两种类型的分子荧 光和磷光 [16,20,38,[117][118][119][120][121][122][123][124][125][126] . 碳点也已经报道了在紫外-可见-近红外整个光谱区域中发光可调, 并观察到来源于碳结 构的准带隙发射 [117][118][119][120][121][122][123] , 但在量子尺寸效应方面仍存在 争议 [20,124] .…”

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