Single-chip horticultural LEDs enabled by greenly synthesized red-emitting carbon quantum dots

• Published in: Materials letters 2023-06, Vol.341, p.134195, Article 134195
• Main Authors: Mai, Xuan-Dung, Nguyen, Sinh-Hung, Tran, Dai-Luat, Nguyen, Van-Quang, Nguyen, Van-Hao
• Format: Article
• Language: English
• Subjects: Agriculture lighting; Carbon quantum dots; Green synthesis; LEDs; Red-emitting
• ISSN: 0167-577X
• DOI: 10.1016/j.matlet.2023.134195

Ethanol extract of bougainvillea leaves was carbonized by a solvothermal method to synthesize red-emitting carbon quantum dots (R-CQD) in which embedded chlorophyll are red-emitting centers. [Display omitted] •The green synthesis of red-emitting quantum dots is presented.•Ethanol extract of bougainvillea leaves was used as a carbon source.•Chlorophyll dyes retained in the quantum dots respond for the red emission.•The use of quantum dots as phosphor in horticultural LEDs is demonstrated. Light emitting diodes (LEDs) having the emission spectra that match the absorption regions of a target plant are strongly demanded for vertical farming. Herein, we demonstrate the use of red-emitting carbon quantum dots (R-CQDs) as a phosphor to fabricate cost-effective horticultural LEDs. R-CQDs having chlorophyll molecules embedded in a carbogenic matrix were solvothermally synthesized using ethanol extract of bougainvillea leaves as a green carbon source. R-CQDs emit a narrow band maximizing at 670 nm originated from the chlorophyll centers when excited either the carbogenic matrix or embedded chlorophyll. R-CQD phosphor converts partially 410 nm light emitted from a LED chip to red and far red regions, thus offering cheaper, single – chip LEDs for agriculture lighting.