Engineering of Aromatic Naphthalene and Solvent Molecules to Optimize Chemical Prelithiation for Lithium-Ion Batteries.

A cost-effective chemical prelithiation solution, which consists of Li, polyaromatic hydrocarbon (PAH), and solvent, is developed for a model hard carbon (HC) electrode. Naphthalene and methyl-substituted naphthalene PAHs, namely 2-methylnaphthalene and 1-methylnaphthalene, are first compared. Grafting an electron-donating methyl group onto the benzene ring can decrease electron affinity and thus reduce the redox potential, which is validated by density functional theory calculations.

Metal-Doped NASICON/Polymer Composite Solid Electrolyte for Lithium Titania Anode in Lithium-Ion Batteries.

This study reports five types of metal-doped (Co, Cu, Sn, V, and Zr) NASICON-type LiAlTi(PO) (LATP)/polymer composite solid electrolytes (CSEs) enabling LiTiO (LTO) anodes to have high rate capability and excellent cycling performance. The high Li-conductivity LATP samples are successfully synthesized through a modified sol-gel method followed by thermal calcination. We find that the cation dopants clearly influence the substitution of Al for Ti, with the type of dopant serving as a crucial factor in determining the ionic conductivity and interfacial resistance of the solid electrolyte.

Synthesis and Characterization of MnInS/Single-Walled Carbon Nanotube Composites as an Anode Material for Lithium-Ion Batteries.

In this study, we synthesized a transition metal sulfide (TMS) with a spinel structure, i.e., MnInS (MIS), using a two-step hydrothermal and sintering process.

Double Nitrogenation Layer Formed Using Nitric Oxide for Enhancing Li Storage Performance, Cycling Stability, and Safety of Si Electrodes.

To enhance Li storage properties, nitrogenation methods are developed for Si anodes. First, melamine, urea, and nitric oxide (NO) precursors are used to nitrogenize carbon-coated Si particles. The properties of the obtained particles are compared.

Assessment of biomass-derived carbon dots as highly sensitive and selective templates for the sensing of hazardous ions.

Access to safe drinking water and a hygienic living environment are the basic necessities that encourage healthy living. However, the presence of various pollutants (especially toxic heavy metal ions) at high concentrations in water renders water unfit for drinking and domestic use. The presence of high concentrations of heavy-metal ions (, Pb, Hg, Cr, Cd, or Cu) greater than their permissible limits adversely affects human health, and increases the risk of cancer of the kidneys, liver, skin, and central nervous system.

Hydrothermal Synthesis of Functionalized Carbon Nanodots and Their Clusters as Ionic Probe for High Sensitivity and Selectivity for Sulfate Anions with Excellent Detection Level.

Nitrogen-doped carbon nanodots (CNDs) were synthesized and utilized as sensing probes to detect different anions and metallic ions within aqueous solutions. The pristine CNDs were developed through a one-pot hydrothermal synthesis. -Phenylenediamine was used as the precursor.

Sodium Super Ionic Conductor-Type Hybrid Electrolytes for High Performance Lithium Metal Batteries.

Composite solid electrolytes (CSEs), composed of sodium superionic conductor (NASICON)-type LiAlTi(PO) (LATP), poly (vinylidene fluoride-hexafluoro propylene) (PVDF-HFP), and lithium bis (trifluoromethanesulfonyl)imide (LiTFSI) salt, are designed and fabricated for lithium-metal batteries. The effects of the key design parameters (i.e.

Specific Forms of Graphene Quantum Dots Induce Apoptosis and Cell Cycle Arrest in Breast Cancer Cells.

Graphene quantum dots (GQDs), nanomaterials derived from graphene and carbon dots, are highly stable, soluble, and have exceptional optical properties. Further, they have low toxicity and are excellent vehicles for carrying drugs or fluorescein dyes. Specific forms of GQDs can induce apoptosis and could be used to treat cancers.

Microwave synthesis of boron- and nitrogen-codoped graphene quantum dots and their detection to pesticides and metal ions.

Through developing a highly efficient solid-phase microwave-assisted (SPMA) synthesis technique, we were able to synthesize graphene quantum dots (GQDs) that were doped with nitrogen and boron atoms. The as-synthesized GQDs were employed as sensing probes for detecting pesticides and iron ions within aqueous solutions. The SPMA approach is very versatile for in-situ doping of multiple atoms within the graphitic structure of GQDs.

Fabrication of Inorganic Coatings Incorporated with Functionalized Graphene Oxide Nanosheets for Improving Fire Retardancy of Wooden Substrates.

Flame-retardant chemicals are frequently used within consumer products and can even be employed as a treatment on the surface of different types of materials (e.g., wood, steel, and textiles) to prevent fire or limit the rapid spread of flames.

Employing functionalized graphene quantum dots to combat coronavirus and enterovirus.

The ongoing COVID-19 (i.e., coronavirus) pandemic continues to adversely affect the human life, economy, and the world's ecosystem.

Hierarchical Carbon Composites for High-Energy/Power-Density and High-Reliability Supercapacitors with Low Aging Rate.

A facile method for preparing hierarchical carbon composites that contain activated carbon (AC), carbon nanospheres (CNSs), and carbon nanotubes (CNTs) for use as the electrode material in supercapacitors (SCs) was developed. The CNS/CNT network enabled the formation of three-dimensional conducting pathways within the highly porous AC matrix, effectively reducing the internal resistance of an SC electrode. The specific capacitance, cyclability, voltage window, temperature profile during charging/discharging, leakage current, gas evolution, and self-discharge of the fabricated SCs were systematically investigated and the optimal CNS/CNT ratio was determined.

Effect of Solvent on Fluorescence Emission from Polyethylene Glycol-Coated Graphene Quantum Dots under Blue Light Illumination.

To explore aggregate-induced emission (AIE) properties, this study adopts a one-pot hydrothermal route for synthesizing polyethylene glycol (PEG)-coated graphene quantum dot (GQD) clusters, enabling the emission of highly intense photoluminescence under blue light illumination. The hydrothermal synthesis was performed at 300 °C using o-phenylenediamine as the nitrogen and carbon sources in the presence of PEG. Three different solvents, propylene glycol methyl ether acetate (PGMEA), ethanol, and water, were used for dispersing the PEG-coated GQDs, where extremely high fluorescent emission was achieved at 530-550 nm.

Hierarchical Lignin-Based Carbon Matrix and Carbon Dot Composite Electrodes for High-Performance Supercapacitors.

This work adopts an efficient chemical-wet method to build a three-dimensional (3D) carbon composite as an electrode material for high-performance supercapacitors (SCs). Carbon dots (CDs), prepared by thermal pyrolysis of citric acid and urea under microwaves at 280 °C, are homogeneously coated onto lignin-based activated carbons (ACs), thus forming the 3D composites possessing an interior surface decorated with CD binding sites. Benefiting from the hydrophilicity and ultrafine size of CDs, the affinity of the electrode surface toward aqueous electrolytes is significantly improved with the addition of CDs, leading to the enhanced effective surface area (i.

Recent progress and future prospects of atomic layer deposition to prepare/modify solid-state electrolytes and interfaces between electrodes for next-generation lithium batteries.

Lithium ion batteries (LIBs) are encouraging electrochemical devices with remarkable properties including a high energy/power density, fast charging capability, and low self-discharge rate. Further increase in energy density as well as safe usage is needed for next-generation LIBs in electric transportation vehicles. Solid-state electrolytes (SSEs) are very promising for high-performance LIBs since they enable improved safety along with increased energy density compared to flammable liquid organic electrolytes.

Polyethylene Glycol/carbon Nanodots as Fluorescent Bioimaging Agents.

Photoluminescent nanomaterials have immense potential for use in biological systems due to their excellent fluorescent properties and small size. Traditional semiconductor quantum dots are heavy-metal-based and can be highly toxic to living organisms, besides their poor photostability and low biocompatibility. Nano-sized carbon quantum dots and their surface-modified counterparts have shown improved characteristics for imaging purposes.

A Holey Graphene Additive for Boosting Performance of Electric Double-Layer Supercapacitors.

We demonstrate a facile and effective method, which is low-cost and easy to scale up, to fabricate holey graphene nanosheets (HGNSs) via ultrafast heating during synthesis. Various heating temperatures are used to modify the material properties of HGNSs. First, we use HGNSs as the electrode active materials for electric double-layer capacitors (EDLCs).

Graphene quantum dot-decorated carbon electrodes for energy storage in vanadium redox flow batteries.

Nitrogen-doped graphene quantum dots (GQDs) and graphitic carbon nitride (g-CN) quantum dots are synthesized via a solid-phase microwave-assisted (SPMA) technique. The resulting GQDs are deposited on graphite felt (GF) and are employed as high-performance electrodes for all-vanadium redox flow batteries (VRFBs). The SPMA method is capable of synthesizing highly oxidized and amidized GQDs using citric acid and urea as the precursor.

Antibacterial Property of Composites of Reduced Graphene Oxide with Nano-Silver and Zinc Oxide Nanoparticles Synthesized Using a Microwave-Assisted Approach.

Graphene oxide (GO) composites with various metal nanoparticles (NPs) are attracting increasing interest owing to their broad scope in biomedical applications. Here, microwave-assisted chemical reduction was used to deposit nano-silver and zinc oxide NPs (Ag and ZnO NPs) on the surface of reduced GO (rGO) at the following weight percentages: 5.34% Ag/rGO, 7.

Tailoring fluorescence emissions, quantum yields, and white light emitting from nitrogen-doped graphene and carbon nitride quantum dots.

Highly fluorescent N-doped graphene quantum dots (NGQDs) and graphitic carbon nitride quantum dots (CNQDs, g-CN) were synthesized using a solid-phase microwave-assisted (SPMA) technique. The SPMA method, based on the pyrolysis of citric acid and urea with different recipes, is capable of producing quantum dots with coexisting NGQDs and CNQDs at 280 °C within only five minutes. The photoluminescence (PL) emissions from NGQD and CNQDs are strongly dependent on the excitation wavelength and the solvent type, i.

Recent Advances and Perspectives of Carbon-Based Nanostructures as Anode Materials for Li-ion Batteries.

Rechargeable batteries are attractive power storage equipment for a broad diversity of applications. Lithium-ion (Li-ion) batteries are widely used the superior rechargeable battery in portable electronics. The increasing needs in portable electronic devices require improved Li-ion batteries with excellent results over many discharge-recharge cycles.

Linear control of the oxidation level on graphene oxide sheets using the cyclic atomic layer reduction technique.

Precise control of the oxidation level on graphene oxide (GO) sheets is still a big challenge. This work demonstrates a linear control of the surface oxidation level on GO sheets via an atomic layer reduction (ALR) technique at 100 and 150 °C. The oxygen stripping rate during ALR cycling was assessed at different operating temperatures: 0.

Supercapacitive Properties of Micropore- and Mesopore-Rich Activated Carbon in Ionic-Liquid Electrolytes with Various Constituent Ions.

Ionic-liquid (IL) electrolytes, characterized by large potential windows, intrinsic ionic conductivity, low environmental hazard, and high safety, are used for micropore- and mesopore-rich activated-carbon (AC and AC ) supercapacitors. IL electrolytes consisting of various cations [1-ethyl-3-methylimidazolium (EMI ), N-propyl-N-methylpyrrolidinium (PMP ), and N-butyl-N-methylpyrrolidinium (BMP )] and various anions [bis(trifluoromethylsulfonyl)imide (TFSI ), BF , and bis(fluorosulfonyl)imide (FSI )] are investigated. The electrolyte conductivity, viscosity, and ion transport properties at the AC and AC electrodes are studied.

Atomic layer oxidation on graphene sheets for tuning their oxidation levels, electrical conductivities, and band gaps.

Graphene sheets that can exhibit electrical conducting and semiconducting properties are highly desirable and have potential applications in fiber communications, photodetectors, solar cells, semiconductors, and broadband modulators. However, there is currently no efficient method that is able to tune the band gap of graphene sheets. This work adopts an efficient atomic layer oxidation (ALO) technique to cyclically increase the oxidation level of graphene sheets, thus, tuning their electrical conductance, band-gap structure, and photoluminescence (PL) response.

Eco-Efficient Synthesis of Highly Porous CoCO Anodes from Supercritical CO for Li and Na Storage.

An eco-efficient synthetic route for the preparation of high-performance carbonate anodes for Li and Na batteries is developed. With supercritical CO (scCO ) as the precursor, which has gas-like diffusivity, extremely low viscosity, and near-zero surface tension, CoCO particles are uniformly formed and tightly connected on graphene nanosheets (GNSs). This synthesis can be conducted at 50 °C, which is considerably lower than the temperature required for conventional preparation methods, minimizing energy consumption.