Carbon Dot/Polymer Composites with Various Precursors and Their Sensing Applications: A Review

Abstract

Carbon dots (CDs) have generated much interest because of their significant fluorescence (FL) properties, extraordinary photophysical attributes, and long-term colloidal stability. CDs have been regarded as a prospective carbon nanomaterial for various sensing applications because of their low toxicity, strong and broad optical absorption, high chemical stability, rapid transfer properties, and easy modification. To improve their functionality, CD/polymer composites have been developed by integrating polymers into CDs. CD/polymer composites have diversified because of their easy preparation and applications in sensing, optoelectronics, semiconductors, molecular delivery, and various commercial fields. Many review articles are available regarding the preparation and applications of CDs. Some review articles describing the production and multiple applications of the composites are available. However, no such article has focused on the types of precursors, optical properties, coating characteristics, and specific sensing applications of CD/polymer composites. This review aimed to highlight and summarize the current progress of CD/polymer composites in the last five years (2017–2021). First, we overview the precursors used for deriving CDs and CD/polymer composites, synthesis methods for preparing CDs and CD/polymer composites, and the optical properties (absorbance, FL, emission color, and quantum yield) and coating characteristics of the composites. Most carbon and polymer precursors were dominated by synthetic precursors, with citric acid and polyvinyl alcohol widely utilized as carbon and polymer precursors, respectively. Hydrothermal treatment for CDs and interfacial polymerization for CDs/polymers were frequently performed. The optical properties of CDs and CD/polymer composites were almost identical, denoting that the optical characters of CDs were well-maintained in the composites. Then, the chemical, biological, and physical sensing applications of CD/polymer composites are categorized and discussed. The CD/polymer composites showed good performance as chemical, biological, and physical sensors for numerous targets based on FL quenching efficiency. Finally, remaining challenges and future perspectives for CD/polymer composites are provided.

Polymer-Induced Emission-Active Fluorine-Embedded Carbon Dots for the Preparation of Warm WLEDs with a High Color Rendering Index

“…Additionally, the H-bond network induces the charge transfer effect from electron-donating to electron-withdrawing groups . This method tends to red-shift the absorption and emission of CDs/PVA. , Other than that, surface PVA chains eliminate the π–π interaction of the conjugated core and construct a self-quenching resistance polymeric system around CDs. As a result, the AQE effect is suppressed in the CD/PVA composite.…”

Stabilization of CsPbBr3quantum dots for photocatalysis, imaging and optical sensing in water and biological medium: a review

“…The introduction of a polymer ligand forms a metal complex with QDs by replacing the original ligand and the new polymer ligand covers the surface to prevent QDs from degradation. 113 These polymer encapsulations are made in situ using polymer beads 114 and polymer gels, 115 which can engulf CPQDs in them, and act as a protective barrier towards all environmental conditions, including heat. Some selective polymers such as poly(styrene-butadiene-styrene) (SBS), poly(methyl methacrylate) (PMMA), polystyrene (PS), and poly(isobutylene-altmaleic anhydride) [116][117][118] can withstand very high temperatures.…”

Optical and Physicochemical Characterizations of a Cellulosic/CdSe-QDs@S-DAB5 Film

“…Different QDs (CdSe, CdTe, CdSe/ZnS, carbon, nitrogen-doped carbon, graphene) and support matrices (poly(methyl methacrylate), polyamide, transparent wood, cellulose, etc.) for electronic devices, solar concentrators, white light-emitting diodes, sensors or agriculture (sunlight conversion films) have already been reported [16][17][18][19][20][21][22][23][24][25]. Among them, regenerated cellulose (RC), a flexible, transparent, biodegradable and low-cost material, exhibits appropriated characteristics for QDs modification [26][27][28][29].…”

“…This kind of hybrid system with tailoring optical parameters can be of interest in different applications (photovoltaic devices, light-emitting devices, etc.) [19,[23][24][25].…”