Bright Electroluminescent White‐Light‐Emitting Diodes Based on Carbon Dots with Tunable Correlated Color Temperature Enabled by Aggregation

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2021-12, Vol.17 (52), p.e2104551-n/a
• Main Authors: Wang, Zhibin, Jiang, Naizhong, Liu, Menglong, Zhang, Ruidan, Huang, Feng, Chen, Daqin
• Format: Article
• Language: English
• Subjects: Agglomeration; aggregation; Black body radiation; Carbon; Carbon dots; Color temperature; Electroluminescence; Light emitting diodes; Nanomaterials; Nanotechnology; Optoelectronics; Quantum efficiency; white‐light‐emitting diodes
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202104551

Carbon dots (CDs) as one of the most promising carbon‐based nanomaterials are inspiring extensive research in optoelectronic applications. White‐light‐emitting diodes (WLEDs) with tunable correlated color temperatures (CCTs) are crucial for applications in white lighting. However, the development of high‐performance CDs‐based electroluminescent WLEDs, especially those with adjustable CCTs, remains a challenge. Herein, white CDs‐LEDs with CCTs from 2863 to 11 240 K are successfully demonstrated by utilizing aggregation‐induced emission red‐shifting and broadening of CDs. As a result, a series of warm white, pure white, and cold white CDs‐LEDs are realized with adjustable emissions in sequence along the blackbody radiation curve. These CDs‐LEDs reach maximum brightness and external quantum efficiency up to 1414–4917 cd m−2 and 0.08–0.87%, respectively, which is among the best performances of white CDs‐LEDs. To the best of the authors′ knowledge, this is the first time that CCT‐tunable white electroluminescent CDs‐LEDs are demonstrated through controlling the aggregation degrees of CDs. A series of warm white, pure white, and cold white electroluminescent carbon dots light‐emitting diodes (CDs‐LEDs)is successfully demonstrated through controlling aggregation degrees of CDs. These CDs‐LEDs exhibit adjustable correlated color temperatures (2863–11240 K) in sequence along the blackbody radiation curve and reach maximum brightness and external quantum efficiency upto 1414–4917 cd m−2 and 0.08–0.87%, respectively.