Pentaacetyl glucose (PAG) is a common and cheap intermediate and has biocompatible, nontoxic, and renewable features. PAG was investigated as a bleach activator for H2O2 in the pretreatment of gray knitting cotton fabric. The bleaching performance of the H2O2/PAG bleaching system was investigated by measuring the CIE whiteness index (WI), H2O2 decomposition rate and bursting strength. By addition of PAG, the WI and H2O2 decomposition rate increased significantly at 70 °C with little damage to the strength. The effects of temperature and pH value on WI were also considered. Due to its environmental advantages, the H2O2/PAG system showed a good applied prospect. By using benzenepentacarboxylic acid as a fluorescent probe for HO· detection, it was found that PAG could strongly promote HO· generation and that the concentration of HO· was closely related to the WI of the fabric. On this basis, a bleaching mechanism of the H2O2/PAG system was proposed.

•The fluorescent probe based on commercial naphthol AS was facilely prepared.•Methacrylate group acts as an electron acceptor and a reactive site for Cys.•High selectivity toward Cys over Hcy and GSH.•Good water solubility and successful application in living cells imaging.A simple and new fluorescent probe (1) for selective detection of cysteine (Cys) in aqueous solution was facilely synthesized. It was developed based on the masking the phenolic OH group in naphthol AS by a methacrylate group, where the methacrylate group acts as an electron acceptor to quench fluorescence of naphthol AS as well as a reactive site for Cys. The conjugate addition/cyclization reaction of Cys toward methacrylate moiety in the probe 1 led to a cleavage of the methacrylate group and release of free naphthol AS, thereby induced a significant enhancement of fluorescence. The present fluorescent probe exhibited high selectivity toward Cys over homocysteine (Hcy) and glutathione (GSH) and worked well in a physiological aqueous medium, allowing a successful application in living cells imaging.Download high-res image (194KB)Download full-size image

Ternary NiCoPd nanocatalyst dispersed on multi-walled carbon nanotubes (CNTs), NiCoPd/CNTs, was synthesized using a simple and green sonochemical method. The as-prepared NiCoPd/CNT hybrids were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma-atomic emission spectrometry (ICP-AES). The electrochemical measurements revealed that the ternary NiCoPd/CNTs exhibited an enhanced electrocatalytic activity for the methanol oxidation reaction (MOR), much superior to those of the binary NiPd/CNT and CoPd/CNT, as well as monometallic Pd/CNT counterparts, which likely resulted from the synergistic function of the dopant metals of Ni and Co.

Titanium dioxide (TiO2)/fullerene hybrid nanocomposite was facilely fabricated by mixing TiO2 and poly-carboxylic acid functionalized fullerene under an ultrasonication–evaporation method. It was found that the TiO2/fullerene composite could serve as an efficient and reusable photocatalyst for degradation of rhodamine B dye under visible light (λ > 400 nm). The as-prepared photocatalyst was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and diffuse reflection spectroscopy (DRS). The degradation experiments revealed that the photocatalytic activity strongly depends on the contents of fullerene from 0.5% to 3% mass ratio. The incorporation of fullerene into TiO2 efficiently extended the absorption spectrum of photocatalyst to visible light region, enhanced the adsorption capacity and degradation efficiency, resulting from a synergistic effect of fullerene and TiO2. The trapping experiments demonstrated that both the photo-generated hole (h+) and the reactive oxygen species such as superoxide anion radical (O2−) were involved in the photocatalytic reaction.TiO2/fullerene nanocomposite was facilely prepared and showed an enhanced visible photocatalytic activity.

•Trisbenzothiazolylphenol was synthesized as a novel ESIPT fluorophore.•Solvent-dependent photophysics was investigated experimentally and theoretically.•Exhibited a NIR solid state ESIPT emission.•White emission was achieved.A new excited-state intramolecular proton transfer (ESIPT) fluorophore, 2,4,6-trisbenzothiazolylphenol (4), was synthesized and its photophysical properties were studied with steady state absorption and emission spectroscopy as well as time-dependent density functional theory calculation. It was found that 4 showed solvent dependent absorption and fluorescence emission. In the nonpolar solvents, ESIPT occurred and only keto tautomer emission at 570 nm was observed, whereas an emission at 510 nm from the deprotonated anion species was observed in polar solvents. With addition of fluoride, the keto emission was quenched, whereas the anion emission was drastically enhanced, making a ratiometric fluorescence sensing of fluoride achievable. In solid state, 4 showed a fluorescence emission at 605 nm, which is longer than those of 2,4-dibenzothiazolylphenol (575 nm) and 4-methyl-2,6-dibenzothiazolylphenol (592 nm) respectively. Thus, the color tuning of solid state ESIPT emission were achieved from green to yellow and near-infrared by extending of the π-conjugation.

•Graphene-ZnO composite was facilely fabricated by a spontaneous reduction.•ZnO enhanced the the sensitivity of electrochemical biosensor.•Simultaneous electrochemical detection of AA, UA and DA.•Good reproducibility and stability.Reduced graphene oxide-zinc oxide (RGO–ZnO) composite was facilely fabricated by a spontaneous reduction of graphene oxide via zinc slice in one-pot approach at room temperature, and used to modify glassy carbon electrode (GCE) for developing of electrochemical biosensor (RGO–ZnO/GCE). The as-prepared RGO–ZnO was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), scanning electron microscopy (SEM) and transmission electron microscope (TEM). It was revealed that the existence of ZnO in RGO–ZnO/GCE largely enhanced the electroactive surface area (EASA) and therefore the sensitivity for electrochemical sensing. In the mixtures of ascorbic acid (AA), dopamine (DA) and uric acid (UA), the biosensor exhibited three well-resolved voltammetric peaks (ΔEAA–DA = 236 mV, ΔEDA–UA = 132 mV, ΔEAA–UA = 368 mV) in the differential pulse voltammetry (DPV) measurements, allowing a simultaneous electrochemical detection of these biomolecules. The liner relationships between current intensities and concentrations were found to be 50–2350 μM, 1–70 μM and 3–330 μM, with detection limits of 3.71 μM, 0.33 μM and 1.08 μM for AA, UA and DA, respectively. The as-prepared RGO–ZnO/GCE biosensor displayed a good reproducibility and stability and was applied for detection of of AA, DA and UA in real plasma and urine samples with satisfying results.

•Three-dimensional (3D) graphene architectures were facilely fabricated by a green and template-free approach.•A effective biosensor for chloramphenicol was developed based on 3D-graphene materials.•The sensor exhibited enhanced sensitivity, excellent anti-interference ability, reproducibility, and stability.•Satisfying recovery results for CAP detection in real drug and milk samples were achieved.Chloramphenicol (CAP), as a broad-spectrum antibiotic, has been worldwide banned for using in the food producing animals due to its overuse may cause severe threats to public health. It is therefore highly desirable to develop facile, selective and sensitive biosensor for CAP detection and monitoring in drug and foodstuff samples. In this work, three-dimensional reduced graphene oxide (3DRGO) architectures were prepared through a green and template-free approach and used as active electrode materials to develop a highly selective electrochemical sensor for CAP detection. The spontaneous reduction and assembly of graphene oxide via zinc foil was completed at room temperature, followed by washing with diluted hydrogen chloride solution, to produce 3DRGO. The as-prepared 3DRGO were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. An electrochemical biosensor for CAP was constructed based on 3DRGO-modified glass carbon electrode (3DRGO/GCE). It was revealed that the present 3DRGO/GCE sensor exhibited a remarkable performance with a detection range of 1–113 μmol L‒1 and a detection limit of 0.15 μmol L‒1 at physiological pH 7.4. Moreover, the sensor showed an excellent selectivity, stability, reproducibility, and satisfying recovery result for CAP detection in real samples.3D graphene architectures have been constructed by a spontaneous reduction of graphene oxide via zinc foil at room temperature, and used as active electrode materials to develop a highly selective electrochemical sensor for chloramphenicol detection.

•Pt nanoflakes were successfully fabricated by a simple electrodeposition approach.•Functionalized fullerene was used as new nanostructured support materials for electrocatalysts.•Novel pyridine-functionalized fulleropyrrolidine supported Pt catalyst (Pt/PyC60) toward MOR was first reported.•Pt/PyC60 exhibited much enhanced electrocatalytic activity and stability for MOR.Pyridine-functionalized fulleropyrrolidine nanosheets are prepared by a fast reprecipitation method under ultrasonication, and used as a novel nanostructured support materials to fabricate Pt catalyst nanoflakes by a simple electrodeposition approach. The as-prepared novel Pt-fullerene hybrid catalyst (Pt/PyC60) exhibits much enhanced electrocatalytic activity and stability for methanol oxidation reaction compared to the unsupported Pt nanoflakes and commercial Pt/C. The introduction of nanostructured fulleropyrrolidine as new support materials not only increases the electrochemically active surface area of catalyst, but also significantly improves the long-term stability. This will contribute to developing functionalized fullerenes as new nanostructured support materials for advanced electrocatalysts in fuel cells.

By combining alloying and supporting approaches, ternary alloy CuFePt nanocatalysts anchored on the reduced graphene oxide (RGO) have been facilely synthesized by using NaBH4 as reductant in an ambient one-pot strategy. The as-prepared CuFePt/RGO hybrids were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy-dispersive spectrometry (EDS), and transmission electron microscopy (TEM). The electrochemical measurements showed that the ternary CuFePt/RGO exhibited a highly enhanced electrocatalytic activity and improved stability for the methanol oxidation reaction (MOR) and formic acid oxidation reaction (FAOR), much superior to those of binary CuPt/RGO and FePt/RGO, and mono-metallic Pt/RGO counterparts. The atomic composition ratios of Cu and Fe in CuFePt/RGO were also optimized to probe their influences on electrocatalytic performance. The straightforward synthesis of ternary CuFePt/RGO provides a promising strategy for development of high-performance Pt alloy catalysts for both MOR and FAOR in fuel cells.

•Green sonochemical synthesis.•Novel hollow CoNiPt alloy nanostructures anchored on carbon nanotubes.•Enhanced electrocatalytic activity for methanol oxidation reaction.•Improved electrochemical stability.Hollow CoNiPt ternary alloy nanostructures loaded on carboxylated multiwalled carbon nanotubes (c-MWCNTs) are facilely synthesized under a sonochemical condition. The as-prepared CoNiPt/c-MWCNTs hybrid exhibits enhanced electrocatalytic activity and improved stability for methanol oxidation reaction (MOR), much superior to the corresponding pure Pt, binary CoPt and NiPt counterparts. The green sonochemical synthesis of CoNiPt/c-MWCNTs composite provides a promising strategy for developing of high-performance Pt-based catalysts for the MOR in fuel cells.

Ternary CuFePd nanocatalysts were anchored on reduced graphene oxide (rGO) by a simple one-pot chemical reduction with NaBH4 at room temperature, and used as a novel CuFePd/rGO electrocatalyst toward the methanol oxidation reaction (MOR). The CuFePd/rGO nanocatalysts were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The electrocatalytic performance for MOR was evaluated by cyclic voltammetry. The as-prepared ternary CuFePd/rGO exhibited improved activity and stability in comparison with Pd/rGO, binary CuPd/rGO, and FePd/rGO. Furthermore, the effects of the Cu to Fe composition ratio on the electrocatalytic performance are also discussed.

•HO generation in H2O2/TAED and H2O2/TBCC systems was proved and detected with a novel fluorescent probe benzenepentacarboxylic acid.•Effect of HO generation on the cotton fabric bleaching performances was further discussed.•Both TAED and TBCC greatly promoted HO yield in alkaline H2O2 systems.•HO plays a significant role in H2O2/TAED and H2O2/TBCC bleaching.•Another bleaching route was proposed that enormous HO was decomposed from peroxide acid and could oxidize size and impurities.The generation of hydroxyl radical (HO) in H2O2/TAED and H2O2/TBCC systems for cotton fabric bleaching was proved and detected with a novel fluorescent probe benzenepentacarboxylic acid (BA). Effect of HO generation on the cotton fabric bleaching performances was further discussed. The results show that HO yield in H2O2/TAED and H2O2/TBCC systems was respectively about 11 and 15 times higher than that in H2O2 system without activators under the same alkali condition. Meanwhile, TAED and TBCC apparently promoted fabric whiteness and H2O2 decomposition rate. As the addition of HO scavenger dimethylsulfoxide (DMSO), fabric whiteness decreased while tensile strength increased. It proves that HO played a significant role in H2O2/TAED and H2O2/TBCC bleaching. Two main bleaching routes were suggested. The present work brought new insight into H2O2/TAED and H2O2/TBCC bleaching mechanism. It is quite instructive to develop efficient and ecological bleaching processes.

A series of alkyl (methyl, ethyl, propyl, butyl) benzoate ester substituted fulleropyrrolidine derivatives (FP1–FP4) were synthesized and their electronic and electrochemical properties were investigated by means of absorption spectra, electronic structure calculation, and cyclic voltammetry (CV), respectively. The LUMO–HOMO energies and energy gaps of fullerene derivatives were estimated by the first reduction potential measured with CV combined with absorption spectra, which are consistent with those obtained from density functional theory (DFT) calculations. It was found that all fulleropyrrolidines showed very similar absorption spectra, orbital energies and redox behaviors, which are comparable with those of well-known phenyl-C61-butyric acid methyl ester (PCBM). The flowerlike supramolecular architectures obtained from the self-assembly of FP1–FP4 in chloroform–alcohol mixture solvents were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). A lamellar structure with a d-spacing of 1.92–2.02 nm that depends on the molecular size, corresponding to the thickness of a bilayer structure, suggested a face-to-face conformation of the substituent of C60 and an interdigitation of the bare C60 side packing. These fulleropyrrolidines have high C60 content, are energetically PCBM-like, and are capable of forming complex flowerlike architectures, which provide fundamental insights into molecular design toward advanced fullerene materials.

•Novel sunlight active photocatalyst Ag@AgSCN was facilely prepared.•Exhibited a higher photocatalytic activity.•Stable in the repeated photocatalytic applications.Ag@AgSCN nanoparticle was developed as a novel sunlight active photocatalyst. It was prepared by a simple precipitation from AgNO3 and NaSCN, followed by a subsequent photo-reduction deposition of metallic Ag on the surface of AgSCN particles. The photocatalyst was characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and UV–vis diffuse reflection spectroscopy (DRS). The as-prepared Ag@AgSCN nanoparticle is efficient and stable for photocatalytic degradation of rhodamine B dye under both the natural sunlight and visible light, without obvious decline of the activity after five repeated cycles. With trapping experiments, the superoxide anion radical (•O2−) involved in the photocatalytic reaction was found to mainly contribute to the elimination of environmental pollutant.Ag@AgSCN nanoparticle was facilely prepared and developed as a novel sunlight active photocatalyst.

A novel fluorescent probe, benzenepentacarboxylic acid (BA), was developed for the quantitative detection of hydroxyl radicals (HO˙) in a simulated hydrogen peroxide (H2O2) bleaching system. Compared to terephthalic acid (TA), a commonly-used fluorescent probe of HO˙ with four possible reaction sites, the present probe has only one reaction site for HO˙ addition that results in the formation of a single fluorescent product, hydroxybenzenepentacarboxylic acid (HBA). The generation of the single pure fluorescent product by BA, rather than mixtures by TA, made the present probe more sensitive, accurate and reproducible in the quantitative detection of HO˙. Based on the working curve obtained from the fluorescence intensity and HBA concentration, a fluorimetric method for the quantitative detection of HO˙ was developed. The present probe BA was successfully used for the quantitative detection of HO˙ under alkaline and high temperature (80 °C) conditions, in a simulated H2O2 bleaching system. The method was highly sensitive, reproducible, and applicable in a wide temperature range of 20–98 °C. The present novel fluorescent probe will be potential tool for evaluating the generation and function kinetics of HO˙ generated in biological and environmental fields.

A facile approach for constructing diverse architectures of unmodified C60 was developed via simple evaporation of pure C60 solution in CS2 under various poor solvent atmospheres. Diverse architectures such as belts, sheets, and starfishes were successfully constructed under different experimental conditions. C60 belts obtained under EtOH atmosphere were confirmed to be a face-centered cubic (fcc) structure. The solvent atmospheres not only slowed down the evaporation speed, but also could reorganize the self-assembly of C60 by partially re-dissolving the initially formed architectures. This concept represents a novel method for preparation of nanostructures of C60 and could also be applied for controlling of the self-assembly of other functional organic molecules.A novel approach was developed for fabrication of various architectures of unmodified C60 solution in CS2 under different poor solvent atmospheres.

A series of substituted para-, meta- and ortho-nitrophenyl derivatives of fulleropyrrolidine were synthesized to investigate the effects of the position of substitution on electronic properties by using steady-state absorption and fluorescence spectra, combined with DFT calculations. The results confirmed that the position of substitution has little effect on absorption and fluorescence spectra, whereas a significant effect was observed on their LUMO energy levels. The theoretical calculations revealed that the LUMO energy of the ortho-nitrophenyl substituted derivative was increased 0.1 eV above those of para- and meta-substitution. The prominent effect of ortho-substitution was attributed to the through-space orbital interaction between spatially closed electron-withdrawing nitro group and fullerene cage. These findings could provide fundamental insights in raising LUMO levels of C60-based electron acceptor materials and an alternative strategy to increase open circuit voltage Voc in polymer solar cells.The through-space orbital interaction between spatially closed ortho-nitrophenyl substituent and fullerene cage efficiently raised the LUMO energy level of fullerene electron-acceptor.

•LUMO levels of fulleropyrrolidines were determined by electrochemical study and DFT calculation.•A linear correlation between the LUMO levels of fulleropyrrolidine and the Hammett constants of substituents installed were established.•Allow to predicting and finely tuning the LUMO level of fullerene electron-acceptor.The LUMO levels of series fulleropyrrolidines equipped with electron-withdrawing and electron-donating groups were determined by electrochemical study and DFT calculation. A linear correlation between the LUMO levels of fullerenes and the Hammett constants of substituents installed was established for the first time. This may allow to predicting and finely tuning the LUMO level of fullerene electron-acceptor.A linear correlation between the LUMO levels of fulleropyrrolidine and the Hammett constants of substituents installed were established.

A novel reversible Hg2+-selective fluorescent chemosensor (1) was constructed based on a thioether linked bis-rhodamine. The sensor was operated in a nearly pure aqueous medium with a broad pH region. The binding mode was proposed based on ESI-MS analysis and DFT calculations.

Fluorescein semicarbazide (1) was synthesized and developed as a novel fluorescent probe for the highly selective and rapid detection of hypochlorite (ClO−) in aqueous solution. The signaling mechanism was proposed based on ESI-MS identification of the oxidation product and captured chlorinated intermediate species.

Two new π-conjugation extended benzothiazole derivatives bearing single (2) or double (3) vinyl groups between benzothiazolyl and 4-methylphenol moieties in 2,6-dibenzothiazolyl-4-methylphenol (1) have been synthesized and their photophysical properties were studied. In nonpolar solvents, 2 showed a keto tautomer emission from the excited state intramolecular proton transfer (ESIPT) at 626 nm, remarkably red-shifted compared to the keto tautomer fluorescence of 1 (568 nm), whereas 3 only exhibited an enol emission at 420 nm. However, a near-infrared (NIR) emission at 616/688 nm for 2/3 from the deprotonated anionic species was observed in polar solvents, which is farther red-shifted compared to that for deprotonated 1 (516 nm). With the aid of computational studies, the experimental observations were rationalized according to the efficient extension of π-conjugation of the molecular backbones in 2 and 3. Furthermore, a white emission with a broad band between 400 and 800 nm from 3 was also observed in a polar–nonpolar solvent mixture, where nearly pure white coordinates (0.33, 0.35) from the CIE chromaticity diagram were successfully achieved. By masking the phenol group in 3, a NIR fluorescent probe (4) for biothiols was constructed, which allows for imaging applications in living cells.

Fluorescein semicarbazide (1) was synthesized and developed as a novel fluorescent probe for the highly selective and rapid detection of hypochlorite (ClO−) in aqueous solution. The signaling mechanism was proposed based on ESI-MS identification of the oxidation product and captured chlorinated intermediate species.