Fabrication of high quantum efficiency nanoscale device is challenging due to increased carrier loss at surface. Low dimensional materials such 0D quantum dots and 2D materials have been widely studied to mitigate the loss. Here, we demonstrate a strong photoluminescence enhancement from graphene/III-V quantum dot mixed-dimensional heterostructures. The distance between graphene and quantum dots in the 2D/0D hybrid structure determines the degree of radiative carrier recombination enhancement from 80% to 800% compared to the quantum dot only structure. Time-resolved photoluminescence decay also shows increased carrier lifetimes when the distance decreases from 50 to 10 nm. We propose that the optical enhancement is due to energy band bending and hole carrier transfer, which repair the imbalance of electron and hole carrier densities in quantum dots. This 2D graphene/0D quantum dot heterostructure shows promise for high performance nanoscale optoelectronic devices.
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http://dx.doi.org/10.1021/acs.nanolett.3c00321 | DOI Listing |
Int J Biol Macromol
January 2025
Department of Materials Engineering, Materials and Energy Research Center, Dezful Branch, Islamic Azad University, Dezfool, Iran.
Polymer-based nanocomposite coatings that are enhanced with nanoparticles have gained recognition as effective materials for antibacterial purposes, providing improved durability and biocidal effectiveness. This research introduces an innovative chitosan-based polymer nanocomposite, enhanced with titanium oxide nanopowders and carbon quantum dots. The material was synthesized via the sol-gel process and applied to 316L stainless steel through dip-coating.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab Pulp & Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, PR China. Electronic address:
Utilizing cellulose nanocrystals (CNCs) to mimic biological skin capable of converting external stimuli into optical and electrical signals represents a significant advancement in the development of advanced photonic materials. However, traditional CNC photonic materials typically exhibit static and singular optical properties, with their structural color and mechanical performance being susceptible to water molecules, thereby limiting their practical applications. In this study, CNC-based conductive elastomers with dynamic mechanochromism, fluorescence responsiveness, and enhanced water resistance were developed by incorporating carbon quantum dots (C QDs) and hydrophobic deep eutectic solvents (HDES) into CNC photonic films via an in-situ swelling-photopolymerization method.
View Article and Find Full Text PDFFood Chem
January 2025
State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, 29 The Thirteenth Road, Tianjin Economy and Technology Development Area, Tianjin 300457, PR China; Research Institute of Food Crops, Xinjiang Academy of Agricultural Sciences, No.403 Nanchang Road, Urumqi, Xinjiang 830091, PR China. Electronic address:
A novel electrochemiluminescence (ECL) sensor based on eco-friendly CN QDs was constructed for the ultrasensitive detection of VK. The synthesized NiCo nanocages (NiCo NCs) with large specific surface area and high catalytic activity were used to effectively load CN QDs, forming the nanocomposites (NiCo NCs@CN QDs) with good luminescent properties. After grafting NiCo NCs@CN QDs onto poly-L-cysteine film, the ECL system achieved multiple signal amplification, which was due to the fact that poly-L-cysteine as a co-reactant accelerator sped up the generation of more SO from SO.
View Article and Find Full Text PDFJ Fluoresc
January 2025
Department of Chemistry, The University of Burdwan, Golapbag, Burdwan, 713104, India.
Nitrogen doped Carbon Quantum Dots (NCQDs) have been synthesized using most economical and easiest hydrothermal process. Here, N-phenyl orthophenylenediamine and citric acid were utilised as a source of nitrogen and carbon for the preparation of NCQDs. The synthesized NCQDs were characterized using experimental techniques like UV - Vis absorption, FT-IR, transmission electron microscopy (TEM), X-ray Diffraction (XRD), EDX, dynamic light scattering (DLS), fluorimeter and time resolved fluorescence spectroscopy.
View Article and Find Full Text PDFJ Fluoresc
January 2025
School of Materials and Chemical Engineering, West Anhui University, Lu'an, Anhui, 237012, China.
Nitrogen@Carbon quantum dots (N@CQDs) are prepared using microwave hydrothermal method, and polyvinylpyrrolidone (PVP) and melamine are used as mixed C source and N source. Microwave reaction conditions of preparing the N@CQDs are 170 ℃ and 3 h. This N@CQDs are are used as fluorescence probe for detection of amino acids.
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