A novel method for fabricating hybrid biobased nanocomposites film with stable fluorescence containing CdTe quantum dots and montmorillonite-chitosan nanosheets

Abstract

A method was presented for fabricating the fluorescent nanocomposites containing CdTe quantum dots (QDs) and montmorillonite (MMT)-chitosan (CS). MMT-CS/CdTe QDs nanocomposites were prepared via a simple, versatile and robust approach combination of covalent and electrostatic assembly methods (Scheme 1). The negatively charged MMT was initially modified with positively charged CS through electrostatic assembly, followed by incorporation of CdTe-QDs into the MMT-CS nanosheets by covalent connections between the amino groups of CS and the carboxylic acid groups of thioglycollic acid (TGA). The X-ray diffraction (XRD), High resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and the FTIR were used to prove the QDs have intercalated into the MMT-CS matrix. The fluorescence emission spectra showed that the MMT-CS/CdTe QDs nanocomposites had the best fluorescence intensity compared with the bare CdTe QDs and CS-QDs.

The Effect of Nanofillers on the Functional Properties of Biopolymer-Based Films: A Review

“…Semiconductor quantum dots (QDs) are attracting increasing attention due to their optical properties and high photostability [133]. Due to their strong tendency of oxidation and agglomeration, it is desirable to improve the compatibility and stability of this type of nanofillers in biopolymers [134]. Graphene quantum dots (GQDs) incorporated in biopolymer films have advantages such as availability, biodegradability, low price, and low production cost, making the nanocomposite films a preferred candidate for use in optoelectronics applications [135].…”

Preparation and characterization of self-assembly hydrogels with exfoliated montmorillonite nanosheets and chitosan

“…In figure 4(a), comparing the FTIR spectra of the hydrogels, MMT and CS, new peaks appeared at 2925 and 2855 cm −1 , which belonged to the antisymmetric and symmetric stretching vibration peak of C-H bond in -CH 2in CS [57,58]. Furthermore, the peak at 3633 cm −1 was typical for Al-OH stretching vibration at the edge of MMTNS [59] and the peak at 1602 cm −1 was the flexural vibration of N-H bond in -NH 2 in CS [60]. This result suggested that MMTNS and CS had composited together.…”

Microwave Enhanced Synthesis of Sulfonated Chitosan-Montmorillonite for Effective Removal of Methylene Blue

“…The results also suggested that some of the hydrogen bonds in the CS structure are demolished, but new ones are formed between the functional groups of CS and Al-OH/Si-OH of MT. The peak at 1040 cm -1 indicates Si-O-Si characteristics, which corresponds to the MT structure [26]. Other related peaks to CS, such as at 1385 cm -1 (corresponds to -NH deformation and -CN vibration stretching), remained unchanged upon modification.…”