Carbon dots (CDs) have a wide range of applications and have drawn great interest in the recent decade. The fabrication and control of CDs with different solubilities are still urgent problems for their practical use. In this paper, aqueous soluble and organic soluble CDs (ACDs, OCDs) were produced by one-pot hydrothermal treatment of a designable waterborne polyurethane (WPU) emulsion. The difference in the solubility and fluorescence of these two kinds of CDs was attributed to the various functional groups on the surface, which were derived from the different segment fragments formed by hydrothermal treatment of a block polymer. It was found that the yields of the ACDs and OCDs could be regulated by means of selecting different soft segments in WPU. The more hydrophobic soft segments could result in an increase of the OCDs and a decrease of the ACDs. While the soft segments were hydrophilic or hydrolysable under hydrothermal conditions, only ACDs were obtained. The ACDs had good fluorescence and showed low cytotoxicity for use in multicolour bio-imaging. The OCDs processed good solubility in a wide range of organic solvents and were suitable for preparing fluorescent composite films with polymers.

•MoS2/Ag nanohybrid was applied as a novel matrix in negative-ion MALDI-TOF MS.•The MoS2/Ag nanohybrid exerted synergistic effect on the detection of small molecules.•The MoS2/Ag nanohybrid showed good signal reproducibility and low background interferences comparing to organic matrices.•MoS2/Ag allows simultaneous analysis of multiple drugs and quantification of acetylsalicylic acid in spiked serum samples.This paper reports a facile synthesis of molybdenum disulfide nanosheets/silver nanoparticles (MoS2/Ag) hybrid and its use as an effective matrix in negative ion matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The nanohybrid exerts a strong synergistic effect, leading to high performance detection of small molecule analytes including amino acids, peptides, fatty acids and drugs. The enhancement of laser desorption/ionization (LDI) efficiency is largely attributed to the high surface roughness and large surface area for analyte adsorption, better dispersibility, increased thermal conductivity and enhanced UV energy absorption as compared to pure MoS2. Moreover, both Ag nanoparticles and the edge of the MoS2 layers function as deprotonation sites for proton capture, facilitating the charging process in negative ion mode and promoting formation of negative ions. As a result, the MoS2/Ag nanohybrid proves to be a highly attractive matrix in MALDI-TOF MS, with desired features such as high desorption/ionization efficiency, low fragmentation interference, high salt tolerance, and no sweet-spots for mass signal. These characteristic properties allowed for simultaneous analysis of eight different drugs and quantification of acetylsalicylic acid in the spiked human serum. This work demonstrates for the first time the fabrication and application of a novel MoS2/Ag hybrid, and provides a new platform for use in the rapid and high throughput analysis of small molecules by mass spectrometry.

In this paper, we report the design, synthesis and properties of novel cross-linked benzocyclobutene resin with m-carborane cages and a siloxane backbone. The synthesis process of the m-carborane derivative containing the benzocyclobutene functional group was simple and efficient. 1H, 13C, and 29Si NMR confirmed the structure of the dibenzocyclobutene-functional m-carborane (DBMC). The novel polymer film was readily fabricated through ring-opening polymerization of the benzocyclobutene unit. Differential scanning calorimetry (DSC) and FT-IR were used to study the curing behavior. Thermogravimetric analysis (TGA) showed that the cured film had outstanding thermal stability. The cross-linked film also exhibited good shape-memory property, and had the capacity to address challenges in advanced aerospace. The boron in the cured DBMC was abundant and showed homogeneous distribution at the microscale. These data imply that the cured DBMC is suitable for use as a neutron shielding material, especially in aerospace applications such as neutron shielding garments.

Poly(styrene-co-maleic anhydride) (PSMA) is an important heat boosting additive of some engineering materials. In this study, functionalized graphene nanosheets were developed and introduced to composite with PSMA through a simple physical blending method. To promote a homogeneous dispersion of graphene in PSMA, graphite oxide (GO) was functionalized with 3-aminopropyltriethoxysilane (APTS) before the reduction. The successful functionalization of reduced graphene oxide (RGO) was confirmed by Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analyses (TGA). This modified RGO was introduced into PSMA, and DMA was employed to investigate the mechanical properties. The results showed that the mechanical storage modulus of PSMA was greatly improved, especially at high temperature. Meanwhile, the thermal stability of PSMA/APTS-RGO was also greatly enhanced.

A new, rapid, sensitive, selective and portable fluorescence detection method for nitroaromatics based on polymer dots (Pdots) had been successfully developed not only in aqueous media but also in the solid state with test strips. The fluorescence quenching rates were proportional to the concentrations of 2,4,6-trinitrophenol (TNP) in the range of 0.2–20.0 μg mL−1 and p-nitrophenol (PNP) in the range of 0.05–6.0 μg mL−1, when Pdots were used as ratiometric fluorescent sensors in aqueous solution. The 3σ limit of detection of PNP reached 18.8 ng mL−1. Compared with polymer-based detection for nitroaromatics in the organic phase, the signal enhancement effect was initially found when Pdots were used to detect nitroaromatics in the aqueous phase. The mechanism of the interaction between Pdots and nitroaromatics was revealed as an electron transfer phenomenon from the electron-rich chromophoric probe to the electron deficient nitroaromatics. The results indicated that Pdots-based detection was particularly suitable for on-site qualitative detection and quantitative analysis of nitroaromatics.

A novel Pd catalyst was designed by affording Pd2+ salt on the surface of functional reduced graphene oxide (FRGO), providing a new cheap and stable in situ prepared palladium catalyst for C–C coupling reactions, including the Heck reaction, Suzuki reaction, C–H bond functionalization reactions of thiophenes, and terminal alkyne C–H activation and homocoupling.

•Au(III) decorated carbon dot cluster (Au(III)/CDC) was synthesized to detect glutathione (GSH) through fluorescence “off–on” approach.•The “off” process was realized by the introduction of Au(III) on luminescent carbon dots (CDs), which formed the Au(III)/CDC and quenched the fluorescence of CDs selectively.•The fluorescence of Au(III)/CDC was recovered selectively by biothiols to achieve the “on” process.•The simple, efficient and low cost “off–on” fluorescent probe was applied to detect GSH in MCF-7 cells with/without the oxygen stress.In this paper, we reported for the first time that Au(III) decorated carbon dot cluster (Au(III)/CDC) was synthesized to detect glutathione through fluorescence “off–on” approach. The “off” process was realized by the introduction of Au(III) on luminescent carbon dots (CDs), which formed the complex of Au(III)/CDC and quenched the fluorescence of CDs efficiently. This “off” process was used to detect Au(III) with the selectivity among 21 metal ions and the limitation was 0.48 μM (S/N=3). Au(III) could be removed from the complex by biothiol in the solution, which restored the fluorescence of CDC to achieve the “on” process. This process was selective for biothiols (especially for glutathione) among saccharides, dopamine and amino acids and the limit of detection was 2.02 μM (S/N=3). Due to the dependence of the fluorescence restoration on the concentration of glutathione, Au(III)/CDC was applied as the fluorescence sensor for detection of glutathione in the solution and cellular cytosol. By referring to the fluorescence change in the solution, the intracellular glutathione with/without oxygen stress was evaluated. As compared with the commercial assay, our Au(III)/CDC based assay was simple, facile and low cost, which would be useful to measure intracellular glutathione at different cellular states.

To improve the utilization efficiency of Au catalyst, triangular Au nanoplates on functional reduced graphene oxide were prepared by a facile method. The products with ultra-low trace amounts of Au afforded high catalytic efficiency for the reduction of 4-nitro phenol. The morphology of the products was controlled by tuning the addition of HAuCl4.

•Monodisperse Au–SiO2 composite nanospheres were synthesized through a one-pot method.•The morphologies and sizes of the composite nanospheres were both controllable.•The nanospheres displayed different SERS effects by adjusting their morphologies.•The products showed high catalytic activity in catalytic reduction of 4-nitrophenol.For improving stability and efficiency of noble metal nanomaterials, a straightforward one-step method was developed to synthesize Au–SiO2 composite nanospheres. Monodisperse hybrid silica nanospheres that had anilino-methyl on the surfaces were prepared first. The as-prepared hybrid silica nanospheres were then used to obtain Au nanocrystal through the redox reaction of HAuCl4 and anilino-methyl. This approach led to a better utilization of Au. By adjusting the surface morphologies and the particle sizes, the functional nanospheres displayed different surface-enhanced Raman scattering effects of Rhodamine 6G. The composite nanospheres showed high catalytic activity and good reusability in catalytic reduction of 4-nitrophenol because of their active gold surface.

Poly(L-lactic acid) (PLLA) is a potential candidate for a new renewable resource, but often suffers from a sharp decrease in the storage modulus and heat distortion resistance when the temperature is higher than 60 °C. In this work, reduced graphene oxide (RGO) was introduced to composite with PLLA, which greatly improved the mechanical properties and heat distortion resistance of PLLA. To assist the blending, RGO was firstly chemically functionalized with N-(aminoethyl)-aminopropyltrimethoxysilane (KH792), to improve its compatibility with PLLA. The storage modulus of the PLLA was enhanced by 1500% (from 20 to 300 MPa) around the glass transition temperature, when only 0.5 wt% KH792–RGO was incorporated. Meanwhile, the heat distortion resistance of the PLLA–KH792–RGO was also greatly improved. An investigation on the rheological behavior of the nanocomposite indicated that a network of RGO had been formed in the nanocomposite, which provided an efficient interface interaction with the PLLA. The enhanced stiffness of the PLLA, by introduction of a functionalized RGO network, was preserved well in the rubber state.

Fluorescent carbon nanoparticles (CNPs) with different core sizes (5, 20, 50 nm) were synthesized in one step by hydrothermal treatment of polyacrylamide. It showed CNPs underwent fast endocytosis into the LnCaP cells. The CNPs had a marked size effect on cellular imaging and the optimal size was about 20 nm.

An easy, novel route to prepare Janus nanoparticles and nano-bowls with tunable shapes has been developed. This approach uses a new kind of monodisperse vinyl-silica nanoparticles as templates to obtain large amounts of uniform Janus particles and nano-bowls (several grams). The efficient method adopts water-based hydrolysis-condensation and seed-emulsion polymerization. The uniform Janus nanoparticles and nano-bowls will display wide potential applications in many fields, such as: chemical sensors, construction of complex superstructures and nano-bioreactors.Graphical abstractAn effective method has been developed using a new type of template for obtaining large amounts of uniform Janus particles and nano-bowls (several grams) with tunable shapes through seed-emulsion polymerization.Research highlights► A new type of template to synthesis eccentrical core–shell nanoparticles. ► Synthesis of uniform Janus nanoparticles with tunable shapes in large amounts. ► Different shapes of nanoparticles (from mushroom-like to bowl-like) can be obtained by hydrofluoric acid etch. ►The bowl-like nanoparticles’ inner and outer surfaces have distinct properties.

Highly monodisperse hybrid spherical silica nanoparticles with diameters ranging from 30 to 200 nm were prepared by a one-step emulsion polymerization in aqueous solution. In contrast with the former method for preparing the hybrid silica materials, our method has three advantages. (1) Through this one-pot route, hybrid silica particles with organic functional groups on the surface are prepared in aqueous solution. (2) The particles are created in a size range of 30−200 nm and highly monodisperse. (3) The size of the particles can be effectively well-defined and precisely controlled depending upon the synthesis conditions such as the concentration of surfactant. Other kinds of organosilane monomers have also been tried in the same way. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and dynamic light scattering (DLS) were performed to elucidate the morphologies of the hybrid silica particles. Thermogravimetric analysis (TGA), 29Si NMR, and 13C NMR were used to gain information about thermal properties and detail structure. This approach may open a new broad avenue for the hybrid material in the field of photocrystal, electronic enveloping.

To improve the utilization efficiency of Au catalyst, triangular Au nanoplates on functional reduced graphene oxide were prepared by a facile method. The products with ultra-low trace amounts of Au afforded high catalytic efficiency for the reduction of 4-nitro phenol. The morphology of the products was controlled by tuning the addition of HAuCl4.

Poly(L-lactic acid) (PLLA) is a potential candidate for a new renewable resource, but often suffers from a sharp decrease in the storage modulus and heat distortion resistance when the temperature is higher than 60 °C. In this work, reduced graphene oxide (RGO) was introduced to composite with PLLA, which greatly improved the mechanical properties and heat distortion resistance of PLLA. To assist the blending, RGO was firstly chemically functionalized with N-(aminoethyl)-aminopropyltrimethoxysilane (KH792), to improve its compatibility with PLLA. The storage modulus of the PLLA was enhanced by 1500% (from 20 to 300 MPa) around the glass transition temperature, when only 0.5 wt% KH792–RGO was incorporated. Meanwhile, the heat distortion resistance of the PLLA–KH792–RGO was also greatly improved. An investigation on the rheological behavior of the nanocomposite indicated that a network of RGO had been formed in the nanocomposite, which provided an efficient interface interaction with the PLLA. The enhanced stiffness of the PLLA, by introduction of a functionalized RGO network, was preserved well in the rubber state.