Recent Advance in Carbon Dots: From Properties to Applications

Abstract

Carbon dots | Cancer | LEDs | Machine-learning-driven synthesis | Nucleic acidsAs a new type of nanomaterial, carbon dots (CDs) have been recognized as a versatile nanoplatform with enormous potential for biomedical and optoelectronic applications because of low cytotoxicity, photostability, biocompatibility and versatility in addition to their tunable photoluminescence. In this review, we aim at updating the latest research on preparation, optoelectronic and chemical properties of CDs as well as their biomedical and optoelectronic applications. We highlight the applications of CDs for stem cell imaging, cell nucleus imaging, two-photon fluorescence imaging, tumor diagnosis and therapy and their optoelectronic applications including light-emitting diodes (LEDs), solar cells and electrocatalysis. Furthermore, we also discuss current challenges and breakthroughs on machine-learning-driven synthesis of CDs as well as nucleic acid detection with an eye towards the future. Finally, we hope that this review will give further impulses to target-oriented research on CDs for biomedical and optoelectronic applications.Hao Wu (left) pursues his Ph.D. under the supervision of Prof. Louzhen Fan at Beijing Normal University. His research interests focus on the synthesis and biomedical applications of carbon quantum dots.Yang Zhang (middle) received his Ph.D. from the Leibniz Institute for Solid State and Materials Research (IFW Dresden). He joined the College of Chemistry, Beijing Normal University in 2019. His research interests focus on the synthesis of carbon nanomaterials and their applications in optoelectronic device and biomedical system.Louzhen Fan (right) is now a chemistry professor of College of Chemistry, Beijing Normal University. She received her Ph.D. in physical chemistry in 1998 under the supervision of Prof. Daoben Zhu and Prof. Yongfang Li from Institute of Chemistry, the Chinese Academy of Sciences, Beijing. Her research interests are focused on the synthesis of novel carbon nanomaterials and their applications in biology and energy.

Solid‐State Red Laser with a Single Longitudinal Mode from Carbon Dots

“…Note that previous CD lasers are mostly based on a whispering gallery cavity or Fabry‐Perot long cavity owing to their ease of fabrication [15, 16] . However, it is difficult to precisely control the light field and to flexibly select the modes in these resonators [51] . In contrast, the planar microcavity structure is uniform and flat, which can effectively reduce incoherent scattering loss [52] .…”

Solid‐State Red Laser with a Single Longitudinal Mode from Carbon Dots

“…[15,16] However,i ti s difficult to precisely control the light field and to flexibly select the modes in these resonators. [51] In contrast, the planar microcavity structure is uniform and flat, which can effectively reduce incoherent scattering loss. [52] Its optical feedback direction can also be consistent with the deviceslight output direction, which helps to enhance the interaction between the light field and the excitons in the light-emitting layer, thus improving light output efficiency.…”

The Transformation of 0-D Carbon Dots into 1-, 2- and 3-D Carbon Allotropes: A Minireview

“…Recently, machine-learning-based techniques have been used to further our knowledge base and understanding of CDs. More importantly, machine learning has been used to gain a further understanding and build experimental models using data and algorithms to correlate the structure–property relationship of CDs [ 139 ]. Thus, machine-learning-based techniques have been used to develop strategies that allow the synthesis of CDs with targeted optical properties [ 140 , 141 ], optimized quantum yields [ 142 ] and high selectivity in gas sensing [ 143 ].…”