Dot Nanocomposites Research Articles

Influence of bridge structure manipulation on the electrochemical performance of π-conjugated molecule-bridged silicon quantum dot nanocomposite anode materials for lithium-ion batteries.

To assess the influence of bridge structure manipulation on the electrochemical performance of π-conjugated molecule-bridged silicon quantum dot (Si QD) nanocomposite (SQNC) anode materials, we prepared two types of SQNCs by Sonogashira cross-coupling and hydrosilylation reactions; one is SQNC-VPEPV, wherein the Si QDs are covalently bonded by vinylene (V)-phenylene (P)-ethynylene (E)-phenylene-vinylene, and the other is SQNC-VPV. By comparing the electrochemical performances of the SQNCs, including that of the previously reported SQNC-VPEPEPV, we found that the SQNC with the highest specific capacity varied depending on the applied current density; SQNC-VPEPV (1420 mA h g-1) > SQNC-VPV (779 mA h g-1) > SQNC-VPEPEPV(465 mA h g-1) at 800 mA g-1, and SQNC-VPV (529 mA h g-1) > SQNC-VPEPEPV (53 mA h g-1) > SQNC-VPEPV (7 mA h g-1) at 2000 mA g-1. To understand this result, we performed EIS and GITT measurements of the SQNCs. In the course of investigating the lithium-ion diffusion coefficient, charge/discharge kinetics, and electrochemical performance of the SQNC anode materials, we found that electronic conductivity is a key parameter for determining the electrochemical performance of the SQNC. Two probable causes for the unique behavior of the electrochemical performances of the SQNCs are anticipated: (i) the SQNC with predominant electronic conductivity is varied depending on the current density applied during the cell operation, and (ii) the degree of surface oxidation of the Si QDs in the SQNCs varies depending on the structures of the surface organic molecules of the Si QDs and the bridging molecules of the SQNCs. Therefore, differences in the amount of oxides (SiO2)/suboxides (SiOx) on the surface of Si QDs lead to significant differences in conductivity and electrochemical performance between the SQNCs.

Asymmetric fabrication and in vivo evaluation of the wound healing potency of electrospun biomimetic nanofibrous scaffolds based on collagen crosslinked modified-chitosan and graphene oxide quantum dot nanocomposites.

Asymmetric scaffolds were developed through electrospinning by utilizing biocompatible materials for effective wound healing applications. First of all, the chitosan surface was modified with decanoyl chloride and crosslinked with collagen to synthesize collagen crosslinked modified-chitosan (CG-cross-CS-g-Dc). Then, the asymmetric scaffolds were fabricated through electrospinning, where the top layer was a monoaxial nanofiber of the PCL/graphene oxide quantum dot (GOQD) nanocomposite and the bottom layer was a coaxial nanofiber having PCL in the core and the CG-cross-CS-g-Dc/GOQD nanocomposite in the shell layer. The formation of monoaxial (∼130 ± 50 nm) and coaxial (∼320 ± 40 nm) nanofibers was confirmed by transmission electron microscopy (TEM). The presence of GOQDs contributed to antioxidant and antimicrobial efficacy. These scaffolds showed substantial antibacterial activity against the common wound pathogens Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The scaffolds exhibited excellent cytocompatibility (MTT assay) and anti-inflammatory behaviour as analysed via the cytokine assay and biochemical analysis. The in vivo wound healing potential of the nanofibrous scaffolds was assessed with full-thickness excisional wounds in a rat model. The scaffolds accelerated the re-epithelialization as well as the collagen deposition, thereby facilitating the wound healing process in a very short span of time (10 days). Both in vitro and in vivo analyses thus provide a compelling argument for the use of these scaffolds as therapeutic biomaterials and their suitability for application in rapid wound regeneration and repair.

Synthesis of AuPt/graphene quantum dots nanocomposites for determination of glucose by photoluminescence spectroscopy

In this study, a novel material, AuPt/graphene quantum dot nanocomposites (AuPt/GQDs NCPs), that have unique optical properties were successfully synthesized.

A novel sandwich impedimetric immunosensor for detection of apolipoprotein-A1 based on the gold nanoparticle-hybridized mercapto-β-cyclodextrin-Pb(II) metal-organic framework.

A novel sandwich electrochemical impedimetric immunosensor was proposed to detect apolipoprotein-A1 (Apo-A1), a common biomarker for bladder cancer. The molybdenum disulfide/graphene quantum dot (MoS2/GQD) nanocomposites were modified on the surface of a glassy carbon electrode (GCE) and used to immobilize the biotinylated antibody (Ab1) with the help of chitosan and glutaraldehyde (denoted as BSA/Ab1/CHIT/MoS2/GQD/GCE). Pb(II)-thiol-β-cyclodextrin metal-organic framework (denoted as Pb-MOF) was synthesized with lead metal ions and thiol-β-cyclodextrin ligands by a one-pot solvothermal method, and then, gold nanoparticles were modified on the surface of Pb-MOF (Pb-MOF-AuNPs) by Au-S bond, which was used as signal label for the recombinant antibody (Ab2). When the immunosensor of BSA/Ab1/CHIT/MoS2/GQD/GCE reacted with Apo-A1, Pb-MOF-AuNPs-Ab2/BSA was connected to the electrode when immunoreaction occurred, and an immune sandwich structure was formed, which led to significantly increased charge transfer resistance of electrochemical probe for ferrocyanide (II)/(III) within the frequency range 10-1 ~ 105Hz at 5 mV amplitude and the potential of 0.180V (vs. SCE). Based on this principle, the quantitative detection of Apo-A1 was established. The relative change of electrochemical resistance and the logarithmic value of Apo-A1 concentration showed a linear relationship with a linear coefficient of 0.9989 in the range 1.00pgmL-1 and 1.00μgmL-1 with the limit of detection of 0.30pgmL-1. The selectivity, repeatability, and other performance of the proposed immunosensor were also investigated. The immunosensor was successfully applied to the detection of real serum and urine samples with recovery in the range 96.4 ~ 109.1% (RSD < 3.8%), indicating that it could be helpful for the clinical diagnosis of bladder cancer.

Lanthanide complexes functionalized carbon dot nanocomposites as lubricant additives for improving tribological performance

A novel nanocomposite, CDs-La-EDTA, was synthesized by bonding carbon dots to the functional sites of rare earth complexes, and its tribological characteristics were evaluated as lubricant additives. The results showed that the mean friction coefficient and the wear scar diameter of lubricating oil containing 0.15 wt% CDs-La-EDTA were reduced by 14% and 22%, respectively, compared with those of the base oil. Furthermore, the dual lubrication mechanism of the nanocomposite was proposed. The rolling or sliding effect of rare earth nanofibrous rods and the mending effect of carbon dot particles contributed to excellent lubrication performance.

Electronic Synaptic Devices with High Thermostability Induced by Embedded Tungsten Disulfide Quantum Dots for Machine Learning

AbstractIf the speed of machine learning is to be improved, devices and systems with strong resistances to various types of internal noise, mainly internal thermal noise, are urgently needed. The successful demonstration of a synaptic device is reported based on a polyimide–tungsten disulfide quantum dot (PI‐WS2 QD) nanocomposite that continued to operate normally after simultaneous exposure of a high temperature of 100 °C. Such excellent performance is attributable to the strong quantum confinement effect of WS2 QDs. The working current of the device and its power consumption are on the orders of nanoamperes and femtojoules, respectively. Undoubtedly, such devices will significantly improve the physical performances of machine learning systems and allow the rapid realization of greatly improving machine learning speed.

A green approach: Eco-friendly synthesis of Gd2Ti2O7/N-GQD nanocomposite and photo-degradation and electrochemical measurement of hydroxychloroquine as a perdurable drug

In this work, gadolinium titanate (GT = Gd2Ti2O7) nanoparticles were synthesized using expired vials of B12 vitamins (reusing the waste) as a capping agent and reductant by a sol–gel technique. Then, GT/N-GQD (nitrogen-doped graphene quantum dots) nanocomposite was prepared by synthesis of N-GQDs in presence of the GT nanoparticles. Next, this nanocomposite was used for photodegradation of hydroxychloroquine sulfate (HCQ) as a multi-function drug with a long half-life during the photocatalytic reactions under visible light. Because of the necessity of measuring the concentration of this drug in human blood serum, tablets, and wastewater, this nanocomposite was utilized as an electrochemical sensor for its detection. Finally, photocatalytic activity of this nanocomposite was approved by 76 % degradation percent of HCQ and the limit of detection (LOD) equals 0.064 nM confirmed that this sensor is the most sensitive sensor prepared for measurement of HCQ, up to now. Since acetaminophen (AC) is one of the most commonly used drugs which is usually consumed along with HCQ, the performance of this sensor was examined in presence of it. The results showed that the presence of AC couldn’t affect the performance of the sensor. The obtained results were supported by a variety of analyses.

Tuning the interfacial charge transfer dynamics of cellulose–graphene quantum dot nanocomposites by edge functionalization

Cellulose-graphene quantum dot (GQD) nanocomposites are emergent new materials for flexible electronics. The quantum yield of photogenerated charge carriers depends on the electronic structure and dynamics of charge transfer at the interface of cellulose–GQD nanocomposites, which is unknown. In the present work, we investigate the properties of cellulose–GQD nanocomposites in terms of functionalization of GQD based on density functional theory calculations with a conductor-like polarizable continuum model (CPCM). The cellulose–GQD nanocomposite has better photoelectric performance than GQD alone. A nonpolar solvent improves the charge transportation of cellulose–GQD nanocomposites. At the high edge coverage, functionalization of GQD with groups containing a CO double bond decreases the absorption intensity and shifts the absorption maxima of the cellulose–GQD nanocomposites to longer wavelengths. On the other hand, functional groups that do not contain a CO double bond have no effect on the absorption spectra of cellulose–GQD nanocomposites at the low edge coverage. Increasing the edge coverage of the NO2 and CHO groups stabilizes the highest occupied orbitals of the GQDs, leading to extraction of holes from the GQDs. Due to the increased solvent reorganization energy, structural flexibility, electronic coupling, and electron–phonon coupling, cellulose–GQD nanocomposites functionalized with either NO2 or CHO exhibit faster hole transfer compared to non-radiative electron-hole recombination.

Silver-Loaded Carbon and Phosphorous Co-Doped Boron Nitride Quantum Dots (Ag@CP-BNQDs) for Efficient Organic Waste Removal: Theoretical and Experimental Investigations.

In this paper, silver-loaded phosphorous and carbon co-doped boron nitride quantum dot (Ag@CP-BNQD) nanocomposites were synthesized using a co-precipitation method followed by a hydrothermal approach. The nanocomposites of Ag@CP-BNQDs were characterized by scanning electron microscopy, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and ultraviolet–visible spectrophotometry. The as-prepared Ag@CP-BNQDs were used for photocatalytic degradation of 10 common organic pollutants, including dyes, pharmaceuticals, and pesticides in aqueous solution under visible light irradiation. The high-performance photocatalysis of Ag@CP-BNQDs proved that Ag@CP-BNQDs is plasmonic and the n–p junction photocatalyst. Theoretical calculations were done to measure the crystals and electronic structures of Ag@CP-BNQDs. Theoretical results showed that loading of Ag behaves as plasmonic sensitizers and co-catalysts and provides extra bands, which make electron movement easier between valance and conduction bands. The mechanism of the charge separation enhancement was postulated. Our findings might deepen our understanding of how sensitizer surface modification works in photodegradation applications.

ZnO/Boron Nitride Quantum Dots Nanocomposites for the Enhanced Photocatalytic Degradation of Methylene Blue and Methyl Orange.

In this study, a heterostructure photocatalyst of ZnO nanoparticles decorated with boron nitride quantum dots (ZnO/BNQDs) was successfully synthesized by a simple solution procedure. The synthesized ZnO/BNQDs show that the BNQDs effectively suppress the recombination of photoinduced electrons and holes and the transfer of holes from ZnO nanoparticles by the formation of a heterojunction. The ZnO/BNQD nanocomposites thus demonstrate superior photocatalytic performances and excellent stability for the degradation of methylene blue (MB) and methyl orange (MO) under UV light irradiation. Based on the obtained results, the possible photocatalytic mechanism is proposed and discussed. Thus, the ZnO/BNQD nanocomposites demonstrate potential as an efficient low-cost photocatalyst for application in the photodegradation of organic dyes in wastewater for environmental remediation.

A strategy to synthesize highly luminescent GdVO4:Eu3+/CDs nanocomposite based on hydrothermal deposition method and its application in anti-counterfeiting

Highly luminescent GdVO 4 :Eu 3+ /carbon dots (CDs) nanocomposite was synthesized by hydrothermal deposition method for the first time. With the use of dialyzed CDs solution as precursor, the synthetized composite shows negligible emission intensity of CDs. On replacing the dialyzed CDs solution with the crude one, highly luminescent composite can be obtained successfully. Based on the analysis of XPS and FT-IR spectra, one can deduce that the existence of a large amount of citrate anions, ethylenediamine cations and polymer-like CDs in the crude CDs solution make it as nutrient solution of CDs, which can not only facilitate growth of CDs on the surface of GVE, but also greatly prevent nitrogen atoms from falling off the particles during the hydrothermal deposition process. For the dialyzed CDs solution, due to the ions and polymer-like CDs being thoroughly dialyzed, the coated CDs are fragile during hydrothermal deposition process. Besides, the effects of different dosages of ammonia on emission intensities of the two composites are studied. Based on the designable patterns for security application, one can think that the highly luminescent composite is one of the most promising candidates in the anti-counterfeiting field. • Highly luminescent GdVO 4 :Eu 3+ /CDs nanocomposite was synthesized by hydrothermal deposition method. • The hydrothermal deposition method was used to synthesize highly luminescent composite related to CDs for the first time. • The crude CDs solution was used as precursor, which acts as the nutrient solution of N-CDs. • The nutrient solution can not only facilitate growth of CDs on the surface of GVE, but also greatly prevents nitrogen atoms from falling off the particles during hydrothermal deposition process. • The prepared composite is one of the most promising candidates in the anti-counterfeiting field.

Directional Formation of Conductive Filaments for a Reliable Organic-Based Artificial Synapse by Doping Molybdenum Disulfide Quantum Dots into a Polymer Matrix.

The conductive filament (CF) model, as an important means to realize synaptic functions, has received extensive attention and has been the subject of intense research. However, the random and uncontrollable growth of CFs seriously affects the performances of such devices. In this work, we prepared a neural synaptic device based on polyvinyl pyrrolidone-molybdenum disulfide quantum dot (MoS2 QD) nanocomposites. The doping with MoS2 QDs was found to control the growth mode of Ag CFs by providing active centers for the formation of Ag clusters, thus reducing the uncertainty surrounding the growth of Ag CFs. As a result, the device, with a low power consumption of 32.8 pJ/event, could be used to emulate a variety of synaptic functions, including long-term potentiation (LTP), long-term depression (LTD), paired-pulse facilitation, post-tetanic potentiation, short-term memory to long-term memory conversion, and "learning experience" behavior. After having undergone consecutive stimulation with different numbers of pulses, the device stably realized a "multi-level LTP to LTD conversion" function. Moreover, the synaptic characteristics of the device experienced no degradation due to mechanical stress. Finally, the simulation result based on the synaptic characteristics of our devices achieved a high recognition accuracy of 91.77% in learning and inference tests and showed clear digital classification results.

Platinum/carbon dots nanocomposites from palm bunch hydrothermal synthesis as highly efficient peroxidase mimics for ultra-low H2O2 sensing platform through dual mode of colorimetric and fluorescent detection

Detection of hydrogen peroxide and glucose in nanomolar level is crucial for point-of-care medical diagnosis. It has been reported that human's central nervous system diseases such as Alzheimer's disease, Parkinson's disease, and even amyotrophic lateral sclerosis, are presumably caused H2O2 or reactive radical species (ROS). Sensing of H2O2 released from human biofluids, tissues, organ from metabolism disorder at ultra-low concentration assists for early identification of severe diabetis mellitus related to glucose, and heart attack, as well as stroke related to cholesterol. In this work, carbon dots (CDs) having an average diameter at 6.99 nm with highly photoluminescence performance were successfully synthesized from palm empty fruit bunch (EFB) using green and environmentally friendly process via hydrothermal condition. CDs acted well on peroxidase-like activity for H2O2 detection at room temperature, however their sensitivity on ultra-low H2O2 concentration needed to be improved. To enhance their reactivity on H2O2 nanozyme activity at room temperature, synthesis of hybrid metal nanoparticles (AgNPs and PtNPs) on CDs surface was established. The findings exhibited that CDs/PtNPs was the most suitable nanozyme achieving highly efficient peroxidase mimic for dual mode of colorimetric and fluorescent H2O2 sensing platform at very low limit of detection of 0.01 mM (10 nM) H2O2.

Preparation of a pH-responsive chitosan-montmorillonite-nitrogen-doped carbon quantum dots nanocarrier for attenuating doxorubicin limitations in cancer therapy.

Despite its widespread usage as a chemotherapy drug in cancer treatment, doxorubicin (DOX) has limitations such as short in vivo circulation time, low solubility, and poor permeability. In this regard, a pH‐responsive chitosan (CS)‐ montmorillonite (MMT)‐ nitrogen‐doped carbon quantum dots (NCQDs) nanocomposite was first developed, loaded with DOX, and then incorporated into a double emulsion to further develop the sustained release. The incorporated NCQDs into the CS‐MMT hydrogel exhibited enhanced loading and entrapment efficiencies. The presence of NCQDs nanoparticles in the CS‐MMT hydrogel also resulted in an extended pH‐responsive release of DOX over a period of 96 h compared to that of CS‐MMT‐DOX nanocarriers at pH 5.4. Based on the Korsmeyer‐Peppas model, there was a controlled DOX release at pH 5.4, while no diffusion was observed at pH 7.4, indicating fewer side effects. MTT assay showed that the cytotoxicity of DOX‐loaded CS‐MMT‐NCQDs hydrogel nanocomposite was significantly higher than those of free DOX (p < 0.001) and CS‐MMT‐NCQDs (p < 0.001) on MCF‐7 cells. Flow cytometry results demonstrated that a higher apoptosis induction achieved after incorporating NCQDs nanoparticles into CS‐MMT‐DOX nanocarrier. These findings suggest that the DOX‐loaded nanocomposite is a promising candidate for the targeted treatment of cancer cells.

Design and fabrication of new anticancer sensor for monitoring of daunorubicin using 1-methyl-3-octylimidazolinium chloride and tin oxide/nitrogen-doped graphene quantum dot nanocomposite electrochemical sensor

In this study, a novel tin oxide/nitrogen-doped graphene quantum dot nanocomposite (SnO2-NDGQD) and 1-methyl-3-octylimidazolinium chloride (1M3OICl) ionic liquid amplified carbon paste electrode (CPE) was fabricated as an efficient and fast-response sensor to determine daunorubicin, an anticancer drug. The electrochemical characteristics of daunorubicin at the surface of the 1M3OICl/SnO2-NDGQD/CPE was explored via various voltammetric methods. The high-resolution transmission electron microscope (HR-TEM) images were recorded to examine the morphological structure of the as-synthesized nanocomposites. The 1M3OICl/SnO2-NDGQD/CPE offered a wide linear concentration of 0.001–280.0 μM with a low detection limit of 0.40 nM at the optimized experimental conditions using square wave voltammetric (SWV) method. In a nutshell, the developed electrode illustrated outstanding selectivity in the presence of interfering agents and long-term stability. The1M3OICl/SnO2-NDGQD/CPE was used as new and powerful analytical tool for determination of daunorubicin in real samples with recovery range 98.75%–104.8%.

Waste biomass-derived CQDs and Ag-CQDs as a sensing platform for Hg2+ ions

Herein, a facile method for the synthesis of carbon quantum dots (CQDs) and silver nanoparticle carbon quantum dots (AgNPs-CQDs) nanocomposites from syzygium cumini leaves by pyrolysis treatment for the sensing of Hg2+ ions is reported. The synthesized CQDs were characterized using UV–visible spectroscopy (217 nm), FTIR, XRD and (HR) TEM. The CQDs measured 4 ± 1 nm (diameter) with 0.32 nm interplanar spacing. The CQDs solution showed bright green photoluminescence upon exposure to UV-light. AgNPs-CQDs exhibited Hg2+ selective colorimetric sensing properties (423 nm) over a wide pH range (4-10). Thus, use of CQDs, especially those generated from waste biomass with in-situ reducing and stabilizing agent, avoids the use expensive and toxic cadium sulfide, cadium selenide and zinc sulfide. The work encapsulates the use of a waste as renewable feedstock (green chemistry principles 1 and 7), avoids the use of toxic reagents and auxiliaries (green chemistry principles 3 and 8), and links to SDG 6 – water and sanitation.

Preparation, Crystallization Behavior, Simultaneous Spectroscopic and Rheological Characterization of Polyphenylene Sulfide/Graphene Quantum Dots Nanocomposites

Front Cover: In article number 2200149 by Weijun Zhen and co-workers, graphene quantum dots (GQDs) are prepared by a low-cost, convenient, and environmentally friendly strategy with brown-black humic acid (BBHA) as a raw material. Then, polyphenylene sulfide (PPS)/GQDs nanocomposites are prepared. GQDs can affect the mechanical properties, crystallization, and rheology of PPS. Simultaneous spectroscopic and rheological characterization of PPS/GQDs nanocomposites are also studied, which may provide a new method to study the crystallization of PPS. In this cover, a part of the schematic diagram of GQDs preparation process is included, and the infrared spectrum during crystallization is also shown.

Photocatalytic removal of pharmaceutical water pollutants by TiO2 - Carbon dots nanocomposites: A review.

Pharmaceuticals are becoming increasingly more relevant water contaminants, with photocatalysts (such as TiO2) being a promising approach to remove these compounds from water. However, TiO2 has poor sunlight-harvesting capacity, low photonic efficiency, and poor adsorption towards organic pollutants. One of the emerging strategies to enhance the photocatalytic performance of TiO2 is by conjugating it with fluorescent carbon dots. Herein, we performed a critical review of the development of TiO2 - carbon dots nanocomposites for the photocatalytic removal of pharmaceuticals. We found that carbon dots can improve the photocatalytic efficiency of the resulting nanocomposites, mostly due to increasing the adsorption of organic pollutants and enhancing the absorption in the visible range. However, while this approach shows significant promise, we also identified and discussed several aspects that need to be addressed before this strategy could be more widely used. We hope that this review can guide future studies aiming to the development of enhanced photocatalytic TiO2 - carbon dots nanocomposites.

Facile synthesis and preparation of graphite/chitosan/graphene quantum dots nanocomposite cathode for electrochemical removal of tetracycline from aqueous solution

In this research, graphene quantum dots (GQDs) was synthesized via the facile pyrolysis method. The properties of the prepared GQDs were examined by high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), dynamic light scattering (DLS), photoluminescence (PL), Fourier transform infrared spectroscopy (FT-IR), and ultraviolet–visible (UV–Vis) methods. Afterward, the graphite/chitosan/graphene quantum dots (Gr/CS/GQDs) nanocomposite was prepared and used as a cathode electrode in electro-Fenton (EF) process to study the tetracycline (TCL) removal from the aqueous solution. The effect of operational parameters in EF, including current density (mA/cm2), initial pH, initial TCL concentration (mg/L), and process time (min) on the TCL removal efficiency, was investigated via response surface methodology (RSM). The results showed that the optimal values for current density, pH, initial TCL concentration, and process time were 60 mA/cm2, 5, 30 mg/L, and 150 min, respectively. Maximum TCL removal efficiency was 92.98%. FT-IR, XRD, Raman spectroscopy, atomic force microscopy(AFM), SEM, mapping, energy dispersive X-Ray (EDX), Brunauer Emmett Teller (BET), and cyclic voltammetry (CV) analyses were performed to investigate the Gr/CS/GQDs cathode. Finally, gas chromatography–mass spectrometry (GC-MS), total organic carbon(TOC), and atomic absorption spectroscopy (AAS) analyses were performed and the reusability of the Gr/CS/GQDs cathode was investigated.

Na2MnPO4F/Ti3C2-CQDs composite cathode material with enhanced electrochemical properties for lithium/sodium hybrid ion battery

Na2MnPO4F and Ti3C2‑carbon quantum dots (CQDs) nanocomposites were prepared by wet mixing method combined with spray drying method, and the two materials were further compounded by heat treatment to get different ratios of Na2MnPO4F/Ti3C2-CQDs cathode material (NTC), the effects of Ti3C2-CQDs on the structure and electrochemical performance of the composite of Na2MnPO4F as a lithium-ion battery cathode material were investigated. The results showed that Na2MnPO4F was uniformly attached to the surface and between layers of Ti3C2-CQDs. The initial specific discharge capacity of NTC-2 at 0.1C was 67.8 mAh·g−1, and the reversible capacity after 100 cycles was 60.7 mAh·g−1, the capacity retention rate was as high as 90%, which all showed that Ti3C2-CQDs can enhance the cycle performance, rate performance and capacity retention rate of Na2MnPO4F. It also showed good rate performance under high current density. After the high current test, the current returned to 0.1C, and the capacity can be restored to the original value, which showed that the material has good structural stability. Therefore, Ti3C2-CQDs doped Na2MnPO4F is an important way to improve the electrochemical performance of polyanionic compounds.