Recent Advances on Graphene Quantum Dots: From Chemistry and Physics to Applications

Abstract

Graphene quantum dots (GQDs) which are flat zero-dimensional nanomaerials, have attracted increasing interest because of their exceptional chemicophysical properties and novel applications in energy conversion and storage, electro-/photo-/chemical catalysis, flexible devices, sensing, display, imaging, and theranostics. In this article, we summarize the significant advances in the recent years with comparative and balanced discussion. We emphasize the difference between GQDs and other nanomaterials including their nanocarbon cousins, and highlight the unique advantages of GQDs for specific applications. The current challenges and outlook of this growing field are also discussed.

Sustainable Synthesis of Bright Green Fluorescent Nitrogen‐Doped Carbon Quantum Dots from Alkali Lignin

“…In contrast, CQDs synthesized by the “bottom‐up” strategy have fewer defects and precise controllability of the structure . This route can produce CQDs from small organic molecules through gradual chemical synthesis, pyrolysis, or carbonization .…”

“…[25] In contrast, CQDs synthesized by the "bottom-up" strategy have fewer defects and precise controllability of the structure. [26] This route can produce CQDs from small organic molecules through gradualc hemical synthesis,p yrolysis, or carbonization. [13,27] Currently,o rganic molecules are generally regarded as the most reliable precursors fort he formation of high-quality CQDs.…”

Recent advances in low‐dimensional semiconductor nanomaterials and their applications in high‐performance photodetectors

“…For example, a very small size creates a quantum confinement effect and makes the bandgap non‐zero. And physical and chemical properties that are easier to regulate, by surface or edge, dopants, and the like . This gives QDs many advantages, including tunable bandgap, good light absorption, tunable photoluminescence (PL), high light stability, and good biocompatibility.…”

“…0D QDs can be obtained from many 2D materials. In addition to B‐P and graphene, TMDs are also an important class of QD materials . Different electronic structures, sizes, thicknesses, and so on, have a great influence on the properties .…”

“…And physical and chemical properties that are easier to regulate, by surface or edge, dopants, and the like. 132 This gives QDs many advantages, including tunable bandgap, good light absorption, tunable photoluminescence (PL), high light stability, and good biocompatibility. It has a good application prospect in the fields of LEDs, PDs, and flexible electronics.…”