Multicolored phosphorescent materials based on carbon dots (CDs) constructed using the same or similar precursors with long lifetimes are conducive to their wide range of practical applications due to the developed compatibility. Herein, a universal method is developed to prepare long-lived multicolored phosphorescent CD-based composites for which heavy-metal doping is not required. The multicolored CDs are encapsulated in silica via silane hydrolysis, which forms many covalent SiOC and SiC bonds; hence, the vibrations and rotations of the luminescent centers on the CD surfaces are hindered. The transformation of SiOC to a more rigid SiC moiety occurs during high-temperature calcination. Furthermore, during calcination, the silica collapses, resulting in more tightly encapsulated CDs. The synergistic effect of these two calcination phenomena produces blue, green, yellow, and red phosphorescence, at wavelengths spanning 465 to 680 nm and with lifetimes of up to 2.11 s. Taking advantage of their superior phosphorescence performances, the CD-based composites are successfully applied to 3D multichannel information storage and encryption.

Rational Design of Covalent Bond Engineered Encapsulation Structure toward Efficient, Long-Lived Multicolored Phosphorescent Carbon Dots.

Traditional room temperature phosphorescence (RTP) materials usually include organometallic composites and pure organic compounds, which generally possess the disadvantages of high toxicity, high cost and complicated preparation. Carbon dots (CDs) are a new kind of luminescent material and have attracted widespread attention due to their benefits of excellent tunable emission, nice biocompatibility, cost-effectiveness, facile preparation and environmental friendliness. Since photoluminescence is an important luminescent property of carbon-based fluorescent nanomaterials, CD-based RTP materials have sparked a new research wave due to the properties of extremely long phosphorescence lifetime, large Stokes shift and high environmental sensitivity. In order to construct excellent CD-based RTP materials, many attempts have been made, and the corresponding progress has been achieved. Herein, we summarize the progress in CD-based RTP materials in recent years, mainly focusing on the outstanding contributions over the years, phosphorescence emission, phosphorescence lifetime, preparation and application of CD-based RTP materials. In particular, this review provides a comprehensive summary and analyze the outstanding contributions in the fields of the phosphorescence emission and phosphorescence lifetime of CD-based RTP materials over the years. Finally, several existing challenges and the future outlook of RTP materials based on CDs have been put forward.

/pdf/evolution-and-fabrication-of-carbon-dot-based-room-wa7vl84k.pdf

Evolution and fabrication of carbon dot-based room temperature phosphorescence materials

Carbon dots (CDs) have gradually become a new generation of nano-luminescent materials, which have received extensive attention due to excellent optical properties, wide source of raw materials, low toxicity, and good biocompatibility. In recent years, there are many reports on the luminescent phenomenon of CDs, and great progress has been achieved. However,there are rarely systematic summaries on CDs with persistent luminescence. Here, a summary of the recent progress on persistent luminescent CDs, including luminous mechanism, synthetic strategies, property regulation, and potential applications, is given. First, a brief introduction is given to the development of CDs luminescent materials. Then, the luminous mechanism of afterglow CDs from room temperature phosphorescence (RTP), delayed fluorescence (DF), and long persistent luminescence (LPL) is discussed. Next, the constructed methods of luminescent CDs materials are summarized from two aspects, including matrix-free self-protected and matrix-protected CDs. Moreover, the regulation of afterglow properties from color, lifetime, and efficiency is presented. Afterwards, the potential applications of CDs, such as anti-counterfeiting, information encryption, sensing, bio-imaging, multicolor display, LED devices, etc., are reviewed. Finally, an outlook on the development of CDs materials and applications is proposed.

Recent Advances of Carbon Dots with Afterglow Emission.

As a type of room temperature phosphorescence (RTP) material, carbon dots (CDs) always show short lifetime and low phosphorescence efficiency. To counter these disadvantages, several strategies, such as embedding in rigid matrix, introducing of heteroatom, crosslink-enhanced emission, etc., are well developed. Consequently, lots of CDs-based RTP materials are obtained. Doping of CDs into various matrix is the dominant method for preparation of long-lived CDs-based RTP materials so far. The desired CDs@matrix composites always display outstanding RTP performances. Meanwhile, matrix-free CDs and carbonized polymer dots-based RTP materials are also widely developed. Amounts of CDs possessing ultra-long lived, multiple colored, and dynamic RTP emission are successfully obtained. Herein, the recent progress achieved in CDs-based RTP materials as well as the corresponding efficient strategies and emission mechanisms are summarized and reviewed in detail. Due to CDs-based RTP materials possess excellent chemical stability, photostability and low biological toxicity, they exhibit great application potential in the fields of anti-counterfeiting, data encryption, and biological monitoring. The application of the CDs-based RTP materials is also introduced in this review. As a promising functional material, development of long wavelength RTP emitting CDs with long lifetime is still challengeable, especially for the red and near-infrared emitting RTP materials.

Long-Lived Dynamic Room Temperature Phosphorescence from Carbon Dots Based Materials.

The power generation humidity sensor has received great attention, however, how to improve its humidity sensing performance (e.g., detection range and response speed) is still facing many challenges. Herein, we propose a simple power generation humidity sensor using NaCl as electrolyte and halloysite nanotubes (HNT) as humidity sensing material. The results show that the introduction of HNT can significantly improve the humidity sensing performance of the humidity sensor based on bare NaCl electrolyte. Specifically, the NaCl/HNT humidity sensor has a wide detection range (10.9 −91.5% relative humidity (RH)), short response time (11.3 s), and good repeatability (20 cycles). The output voltage of the NaCl/HNT humidity sensor reaches 0.537 V at 91.5% RH, and the corresponding maximum power is 1.56 μW. In addition, the NaCl/HNT humidity sensors with series integration can charge the capacitor at high humidity, and the NaCl/HNT humidity sensor can be used for monitoring respiratory patterns. This work provides a useful strategy for fabricating high-performance power generation humidity sensor. 

Power generation humidity sensor based on NaCl/halloysite nanotubes for respiratory patterns monitoring

Triplet excitons usually do not emit light under ambient conditions due to the spin-forbidden transition rule, thus they are called dark excitons. Herein, triplet excitons in carbon nanodots (CNDs) are brightened by embedding the CNDs into poly(vinyl alcohol) (PVA) films; flexible multicolor phosphorescence films are thus demonstrated. PVA chains can isolate the CNDs, and excited state electron or energy transfer induced triplet exciton quenching is thus reduced; while the formed hydrogen bonds between the CNDs and PVA can restrict vibration/rotation of the CNDs, thus further protecting the triplet excitons from nonradiative recombination. The lifetimes of the flexible multicolor phosphorescence films can reach 567, 1387, 726, and 311 ms, and the longest-lasting phosphorescence film can be observed by naked eyes for nearly 15 s even after bending 5000 times. The phosphorescence films can be processed into various patterns, and a dynamic optical signature concept has been proposed and demonstrated based on the phosphorescence films.

Brighten Triplet Excitons of Carbon Nanodots for Multicolor Phosphorescence Films.

Carbon Nanodot-Based Humidity Sensor for Self-Powered Respiratory Monitoring

It remains a challenge to obtain biocompatible afterglow materials with long emission wavelengths, durable lifetimes, and good water solubility. Herein we develop a photooxidation strategy to construct near-infrared afterglow carbon nanodots with an extra-long lifetime of up to 5.9 h, comparable to that of the well-known rare-earth or organic long-persistent luminescent materials. Intriguingly, size-dependent afterglow lifetime evolution from 3.4 to 5.9 h has been observed from the carbon nanodots systems in aqueous solution. With structural/ultrafast dynamics analysis and density functional theory simulations, we reveal that the persistent luminescence in carbon nanodots is activated by a photooxidation-induced dioxetane intermediate, which can slowly release and convert energy into luminous emission via the steric hindrance effect of nanoparticles. With the persistent near-infrared luminescence, tissue penetration depth of 20 mm can be achieved. Thanks to the high signal-to-background ratio, biological safety and cancer-specific targeting ability of carbon nanodots, ultralong-afterglow guided surgery has been successfully performed on mice model to remove tumor tissues accurately, demonstrating potential clinical applications. These results may facilitate the development of long-lasting luminescent materials for precision tumor resection. 

Photooxidation triggered ultralong afterglow in carbon nanodots

Advanced sustainable biomedical materials are urgently needed for clinical applications; however, developing biomedical materials with exceptional mechanical and bactericidal properties as well as removable functionalities to reduce unintended secondary injury remains a challenge. Here, we report a biomass‐derived composite consisting of water‐soluble fish gelatin (FG) and antibacterial ZnO@silk fibroin (ZSF) microspheres for potential application as the wound dressing. The ZSF microspheres are embedded in a FG matrix to realize the stretchable, antibacterial, and removable ZSF/FG composites. By introducing glycerin as the plasticizer, ZSF/FG composites deliver a tensile strength of 4.5 MPa and stretchability of 550%. Acting as both the germicide and hydrophile components, ZSF microspheres endow the composites with excellent antibacterial capacity and water solubility. To prevent secondary injury, the ZSF/FG composites can be easily removed from the wounds by simply exposing them to excess water. Additionally, the ZSF/FG composites exhibit favorable biocompatibility and sustain high cell viability of over 100%. The full‐thickness skin wound model on infected mice demonstrated an efficient rate of wound closure and a reduced inflammatory response. The ZSF/FG composite shows promise to hasten the healing of infected wounds and is expected a promising candidate as wound dressing for clinical therapy.

Biomass‐derived washable composites for accelerating the healing of infected wounds

Continuous synthesis of ultra-fine fiber for wearable mechanoluminescent textile

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Yuan Deng

Author Tools

Chat about Author