Multi-functional ratiometric detection based on dual-emitting N-doped carbon dots.

Ratiometric fluorescence probes based on multi-emission carbon dots improve accuracy and sensitivity on detecting various environment issues. Herein, a novel dual-emitting N-doped carbon dots (N-CDs) was synthesized from citric acid and urea via a solvothermal method in N,N-dimethylformamide (DMF). The blue and orange emissions of N-CDs in water were modulated, and pure white light-emitting with Commission Internationale de L'Eclairage (CIE) coordinates of (0.

Heating-free synthesis of red emissive carbon dots through separated processes of polymerization and carbonization.

Polymerization and carbonization are believed as two basic processes for the bottom-up synthesis of carbon dots (CDs). Since these two processes usually occur simultaneously due to the high reaction temperature and fast reaction rate, it is still a challenge to separate and control these two processes. In the present work, we reported a new room temperature method, which achieved the separated and controlled polymerization and carbonization processes.

Lead-Free Copper-Based Perovskite Nanonets for Deep Ultraviolet Photodetectors with High Stability and Better Performance.

Considering practical application and commercialization, the research of non-toxic and stable halide perovskite and its application in the field of photoelectric detection have received great attention. However, there are relatively few studies on deep ultraviolet photodetectors, and the perovskite films prepared by traditional spin-coating method have disadvantages such as uneven grain size and irregular agglomeration, which limit their device performance. Herein, uniform and ordered CsCuI nanonet arrays are fabricated based on monolayer colloidal crystal (MCC) templates prepared with 1 μm polystyrene (PS) spheres, which enhance light-harvesting ability.

Sandwich-type CoSe-CNWs@rGO/S composites with efficient trapping and catalytic conversion of polysulfides in lithium-sulfur batteries.

Although lithium-sulfur batteries (LSBs) are very promising in energy storage devices, their low conductivity, shuttle effect, and volume expansion unfavorably lead to sluggish kinetics and worsening electrochemical performance. To address these problems, we firstly prepared conductive carbon nanowires embedded with lithiophilic CoSe nanoparticles (CoSe-CNWs), and utilized CoSe-CNWs to construct reduced graphene oxide (rGO) sheets; thereby, sandwich-type CoSe-CNWs@rGO composites were assembled. CoSe-CNWs@rGO composites were taken as the sulfur host.

Employing synergetic effect of ZnSe quantum dots and layered Ni(OH)to boost the performance of lithium-sulfur cathodes.

The low sulfur utilization, cycling instability, and sluggish kinetics are the critical obstructions to practical applications of lithium-sulfur batteries (LSBs). Constructing sulfur hosts with high conductivity, suppressed shuttle effect, and rapid kinetics is essential for their practical application in LSBs. Here, we synthetically utilized the merits of ZnSe quantum dots (QDs) and layered Ni(OH)to boost the performance of LSBs.

Bi and Sb Codoped CsAgNaInCl Double Perovskite with Excitation-Wavelength-Dependent Dual-Emission for Anti-Counterfeiting Application.

The growing demands for optical anti-counterfeiting technology require the development of new environmentally friendly materials with single component, multimodal fluorescence and high stability. Herein, the Bi/Sb codoped CsAgNaInCl lead-free double perovskite material is reported as an efficient multimodal luminescence material with excitation-wavelength-dependent emission. When excited by 360 nm UV light, dual-emission is observed at 455 and 560 nm, which comes from the P-S transition of Sb ions and self-trapped excitons (STEs), respectively.

A special core-shell ZnS-CNTs/S@NH cathode constructed to elevate electrochemical performances of lithium-sulfur batteries.

Lithium-sulfur batteries (LSBs) are regarded as promising candidates for next-generation electrochemical energy storage systems due to their low cost and high energy density. However, the insulative sulfur, the volume expansion and high soluble polysulfides are three roots impeding their practical applications, and consequently bring challenges of low sulfur utilization, poor cyclic stability and sluggish redox kinetics. Herein, a special core-shell ZnS-CNTs/S@Ni(OH) (labeled as ZnS-CNTs/S@NH) cathode has been designed to overcome above obstacles and elevate the electrochemical performance.

Precise control of the ratiometric fluorescence of dual-emissive B/N-doped carbon dots using pH-dependent bonds.

Precise control of the structure and bonds of doped carbon dots (CDs) is important, so that their fluorescence can be tuned as desired. Up until now, there has been a lack of effective ways to control the bonds of doped CDs. In this article, we show that the fluorescence of B/N-doped carbon dots (B/N-CDs) can be precisely tuned just by controlling their precursors' pH values.

Incorporation ZnS quantum dots into carbon nanotubes for high-performance lithium-sulfur batteries.

Constructing sulfur hosts with high electronic conductivity, large void space, strong chemisorption, and rapid redox kinetics is critically important for their practical applications in lithium-sulfur batteries (LSBs). Herein, by coupling ZnS quantum dots (QDs) with carbon nanotubes (CNTs), one multifunctional sulfur host CNT/ZnS-QDs is designed via a facile one-step hydrothermal method. SEM and TEM analyses reveal that small ZnS-QDs (<5 nm) are uniformly anchored on the CNT surface as well as encapsulated into CNT channels.

Improving power conversion efficiency in luminescent solar concentrators using nanoparticle fluorescence and scattering.

Large-size luminescent solar concentrators (LSCs), which act as a complement to silicon-based photovoltaic (Si-PV) systems, still suffer from low power conversion efficiency (PCE). How to improve the performance of LSCs, especially large ones, is currently a hot research topic. Traditional LSCs have only a single transmission mode of fluorescence from the luminescent materials to the Si-PV, but here we introduce a new idea to improve the absorption of Si-PV by employing dual transmission modes of both fluorescence and scattering light.

Self-Assembled Vanadium Oxide Nanoflakes for p-Type Ammonia Sensors at Room Temperature.

VO₂(B), VO₂(M), and V₂O₅ are the most famous compounds in the vanadium oxide family. Here, their gas-sensing properties were investigated and compared. VO₂(B) nanoflakes were first self-assembled via a hydrothermal method, and then VO₂(M) and V₂O₅ nanoflakes were obtained after a heat-phase transformation in nitrogen and air, respectively.

Dendrimer ligands-capped CHNHPbBr perovskite nanocrystals with delayed halide exchange and record stability against both moisture and water.

CHNHPbBr perovskite nanocrystals (NCs) suffer from poor stability because of their high sensitivity to environmental moisture and water. To solve this problem, previous works mainly focus on embedding perovskite NCs into water-resistant matrix to form large composites (size of microns or larger). As an alternative solution without serious changing of NC size, enhancing the stability of perovskite NCs themselves by ligand engineering is rarely reported.

Single component Mn-doped perovskite-related CsPbClBr nanoplatelets with a record white light quantum yield of 49%: a new single layer color conversion material for light-emitting diodes.

Single component nanocrystals (NCs) with white fluorescence are promising single layer color conversion media for white light-emitting diodes (LED) because the undesirable changes of chromaticity coordinates for the mixture of blue, green and red emitting NCs can be avoided. However, their practical applications have been hindered by the relative low photoluminescence (PL) quantum yield (QY) for traditional semiconductor NCs. Though Mn-doped perovskite nanocube is a potential candidate, it has been unable to realize a white-light emission to date.

Fast doping of Cu into ZnSe NCs by hydrazine promoted cation exchange in aqueous solution at room temperature.

Controllable doping is an effective way of tuning the properties of semiconductor nanocrystals (NCs). In this work, a simple strategy of fast doping Cu ions into ZnSe NCs under ambient conditions was proposed. The principle of doping is based on hydrazine (N2H4) promoted cation exchange reaction.

Hydrazine-promoted sequential cation exchange: a novel synthesis method for doped ternary semiconductor nanocrystals with tunable emission.

Using ZnSe nanocrystals (NCs) as starting material, Ag-doped or Cu-doped ZnCdSe ternary NCs were prepared by hydrazine-promoted sequential cation exchange in aqueous media. The composition of the NCs can be flexibly controlled by varying the amount of intermediate Ag or Cu cation addition, thus changing the emission of the ternary NCs while preserving the NC size. According to Vegard's law, the as-prepared ternary NCs possess an alloyed structure.

One-pot synthesis of multicolor MnSe:ZnSe nanocrystals for optical coding.

Though the investigation on controlling the fluorescence properties of nanocrystals (NCs) with single emission has been widely reported, few efforts were spent on adjusting the fluorescence properties of NCs with multiple emission peaks. In this work, we successfully synthesized multicolor MnSe:ZnSe NCs with multiple emission peaks and developed a simple and accurate method to realize photoluminescence (PL) spectra (or color) adjustment. The PL of MnSe:ZnSe NCs has two distinct emission peaks, the trap emission of ZnSe at 475nm and Mn(2+)-induced emission at 585nm.

Automatically purification of aqueous CdTe nanocrystals in water-ethanol co-environment.

Purification is a separated post-treatment step after the synthesis of nanocrystals (NCs) in order to exclude excess ligands and monomers in NC solution. The common purification process involves many manipulations, such as concentrating, addition of anti-solvents and centrifugation, which are troublesome and time consuming. In this work, we originally integrate NC synthesis and NC purification in one-pot via selecting water-ethanol co-environment for NC synthesis and NC purification.

A facile method for gold decoration of Te@CdTe nanorods in aqueous solution.

Colloidal synthesis of metal-semiconductor hybrid nanostructures is mainly achieved in organic solution. In some applications of hybrid nanoparticles relevant in aqueous media, phase transfer of hydrophobic metal-semiconductor hybrid nanostructures is essential. In this work, we present a simple method for direct synthesis of water-soluble gold (Au) decorated Te@CdTe hybrid nanorods (NRs) at room temperature by using aqueous Te@CdTe NRs as templates, which were preformed by using CdTe nanocrystals (NCs) as precursor in the presence of hydrazine hydrate (N(2)H(4)).

Microwave-assisted synthesis of fluorescent Ag nanoclusters in aqueous solution.

Fluorescent Ag nanoclusters are of significant interest because they provide the bridge between atomic and nanoparticle behavior in noble metals. Herein, microwave irradiation was originally used for the synthesis of water-soluble fluorescent Ag nanoclusters. As-prepared Ag nanoclusters present red fluorescence emission around 608 nm and a characteristic absorption peak at about 508 nm.

Aqueous synthesis of internally doped Cu:ZnSe/ZnS core-shell nanocrystals with good stability.

To prepare biologically available Zn-based NCs in aqueous solution, we herein reported the synthesis of aqueous Cu:ZnSe/ZnS NCs with internally doped aqueous Cu:ZnSe NCs as the core template. Due to the dual protection of Cu impurities by the ZnSe core and ZnS shells, the as-prepared Cu:ZnSe/ZnS NCs show excellent stability in the open air, which overcomes the intrinsic instability of traditional aqueous Cu:ZnSe NCs. The as-prepared Cu:ZnSe/ZnS NCs possess extremely good stability, good biocompatibility and lower cytotoxicity, and thus can be used as a promising candidate for fluorescent NC-based biological applications.

Metal-enhanced fluorescence of CdTe nanocrystals in aqueous solution.

Metal-enhanced fluorescence of semiconductor nanocrystals (NCs) is investigated. There is very little attention paid to the metal-enhanced fluorescence in aqueous solution, which has great potential applications in bioscience. In this work, we directly observe metal-enhanced fluorescence of CdTe NC solution by simply mixing CdTe NCs and Au nanoparticles, both of which are negatively charged.