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Biomass materials show great potential in replacing mineral carbon source to fabricate novel high-energy electrode materials. However, it is greatly challenging to prepare core-shell carbon hybrid materials with homogeneous dispersion and high tap density features from biomass since biomass-carbons often exhibit blocky structure. Herein, we facilely fabricate the core-shell microcubes of MnO@C (CCM, average size of ∼5 μm) composite with high tap density of 2.17 g cm−3 using natural agaric as raw materials through simple hydrothermal treatments and calcination process. And the formation mechanism of core-shell microcube structures is analysized by the phase separator theory. It is found that the high-tap-density CCM composite with the stable porous carbon shell (∼1 μm) greatly contributes to accommodate the volume change of MnO active material during lithiation/delithiation process and enable rapid electron/ion transport. As expected, the CCM electrode offers a superhigh volumetric capacity of 1628.7 mAh cm−3, the high reversible capacity (1147 mAh g−1 at 0.1 A g−1), outstanding rate performance (552 mAh g−1 at 2 A g−1) and cycling stability (802 mAh g−1 after 950 cycles at 1 A g−1). We believe that the facile and low-cost biomass-intervened strategy is feasible to fabricate practical core-shell structured metal oxide@carbon composites for efficient electrochemical energy storage.

The capacitive properties of asymmetric supercapacitors (ASCs) are inseparable from the development of anode and cathode materials, which usually required high accessible surface area and uniform p...

Bacterial infection has been a critic problem for implant infections. Poly(L-lactide) (PLLA) membrane has great potential for Guided bone regeneration (GBR), however, PLLA lack antibacterial property and thus may face bacterial infections. In this work, a mussel inspired method was used to treat PLLA membrane with dopamine and formed polydopamine (PDA) coated PLLA (PLLA@PDA), and then silver Nanoparticles (AgNPs) was immobilized on the surface of PLLA via the reduction effect of PDA. The XPS results showed that the silver element contents may be tuned from 1.6% to 15.4%. The AgNPs coated PLLA (PLLA@Ag) showed good antibacterial property (98.3% bactericidal efficiency may be obtained) and good biocompatibility, implying that the PLLA@Ag membrane have potential application as antibacterial GBR membrane, which may enhance the application of PLLA.

Although cobalt sulfide is a promising electrode material for supercapacitors, its wide application is limited by relative poor electrochemical performance, low electrical conductivity, and inefficient nanostructure. Here, we demonstrated that the electrochemical activity of cobalt sulfide could be significantly improved by Al doping. We designed and fabricated hierarchical core-branch Al-doped cobalt sulfide nanosheets anchored on Ni nanotube arrays combined with carbon cloth (denoted as CC/H-Ni@Al-Co-S) as an excellent self-standing cathode for asymmetric supercapacitors (ASCs). The combination of structural and compositional advantages endows the CC/H-Ni@Al-Co-S electrode with superior electrochemical performance with high specific capacitance (1830 F g–1/2434 F g–1 at 5 mV s–1/1 A g–1) and excellent rate capability (57.2%/72.3% retention at 1000 mV s–1/100 A g–1). The corresponding all-solid-state ASCs with CC/H-Ni@Al-Co-S and multilayer graphene/CNT film as cathode and anode, respectively, achieve a ...

The efficient exploitation and utilization of low-cost and biomass-derived carbon materials will play an active role in developing sustainable energy storage systems. However, the difficult morphology control and incomplete activation limits their pervasive application in electrochemical energy storage. Inspired by the famous Chinese folk handicraft of sugar-figure blowing, biomass-derived carbon aerogels (GCA) with 2 D graphene-like thin nanosheets were fabricated by a simple chemical blowing strategy from a viscous agaric solution obtained through hydrothermal treatment of agaric. A chemical blowing agent (NH4 Cl) was used to effectively exfoliate the bulk biomass-derived carbon flake into 2 D graphene-like nanosheets, which resulted in a highly porous structure and high specific area (2200 m2 g-1 ) after the activation process. As a result, a high specific capacitance of 340 F g-1 at 3 A g-1 and a high specific energy of 25.5 Wh kg-1 at a power density of 2 kW kg-1 was obtained for the GCA electrode, which can be attributed to the abundant electrochemically active surfaces, short ion transport paths, and effective electrolyte infiltration.. This work demonstrates an effective and low-cost strategy to prepare hierarchical and well-organized porous biomass carbon materials with graphene-like nanosheets for high-performance supercapacitors.

Due to the deficiency of low melting point and poor wettability of commercial polyolefin separators, the design and development of ceramic coating separators have been received more and more attention in Li-ion batteries recently. However, it is challenging to solve the disadvantageous exfoliation issue of ceramic coating during charge/discharge cycles and needs to be addressed urgently. Herein, a covalent grafting interface engineering strategy has been proposed to prepare a highly efficient and stable polypropylene/mSiO2 separator (PP-g-mSiO2) by the nanoscale mSiO2 layer anchoring on the surface of PP separator with covalent bonding. As expected, the covalent bonding force increase the interfacial stability of PP-g-mSiO2 separator and the mSiO2 NPs facilitate more storage of electrolyte, which results in high thermal stability, high electrolyte affinity and swift lithium-ion diffusion. When used as the separator in LIBs, the Li/LiFePO4 cell with PP-g-mSiO2 separator exhibits excellent rate capability with a discharge capacity of 101 mA h/g at 5 C and remains high capacity retention of 93% after 1000 continuous charge–discharge cycles, which suggests that the PP-g-mSiO2 separator possesses a stable and covalent grafting ceramic surface and have greater affinity to electrolyte, resulting in quicker lithium-ion diffusion and excellent cycling stability. Therefore, the covalent grafting interface modification has confirmed an effective strategy to block exfoliation issues of ceramic coating and developed the high-performance ceramic separators for LIBs.

A critical challenge in the preparation of reinforced polymer nanocomposites is to prevent the aggregation of nanofillers. In this work, a novel poly(γ-benzyl-L-glutamate) (PBLG)-modified silicon dioxide@graphene oxide nanofiller (SiO2@GO-g-PBLG) was prepared via a continuous electrostatic complex and ring-opening polymerization (ROP) method. The grafted PBLG prevented the aggregation of SiO2 nanoparticles and GO sheets, realized the colloid stability of SiO2@GO-g-PBLG in organic solvents, and thus increased its phase interaction in a polymer matrix. The hybrid nanofiller greatly enhanced the mechanical properties of poly(L-lactide) (PLLA). As a typical feature, the tensile strength of PLLA nanocomposites with only 5 wt% of SiO2@GO-g-PBLG was 88.9 MPa, about 45% higher than that of pure PLLA. In addition, the hybrid nanofillers also have some positive effects on improving the thermal stability of PLLA. Therefore, SiO2@GO-g-PBLG was a promising hybrid nanofiller to reinforce polymers such as PLLA.

The lithium metal anode has extremely high theoretical specific capacity and most negative electrochemical potential. However, upon cycling, the formed dendrites result in severe safety concerns and poor stability, thus limiting the applications of the material. Herein, we report a novel separator with excellent lithiophilicity and strength obtained via in-situ modification of virgin cellulose paper (CP) with polydopamine (PDA) to effectively stabilize the Li metal anode. The as-obtained PDA-CP separator showed excellent thermal stability and high mechanical strength due to the interaction between PDA and cellulose molecule, and an excellent electrolyte affinity to enable high electrolyte uptake and ionic conductivity. More importantly, in symmetric Li/Li cells with the PDA-CP separator, the Li metal anode was stabilized during repeated stripping/plating processes over 500 cycles (3000 h) at a current density of 0.5 mA cm−2. Further, we achieved excellent cycling stability over 600 cycles at the rate of 5 C by employing Li/PDA-CP/LiFePO4 cells. The results demonstrate the immense potential of PDA-CP as advanced separator and propose an efficient and simple strategy to stabilize Li metal anode for the next-generation high-energy lithium-metal batteries.

Carbon nanotube (CNT) has aroused much attention in biomedical field. However, the cytotoxicity and aggregation are critical factors that affect the application of carbon nanotube (CNT). Herein, gelatin was grafted on the surface of CNT via mussel-inspired method. The gelatin modified CNT can disperse homogeneously in water. The in vitro test showed that gelatin modified CNT showed much better biocompatibility than the native CNT, which may improve its potential application in biomedical field.

Poly(L-glutamic acid)(PLGA) was grafted onto the surface of mesoporous silica nanoparticles(MSN) via the ring opening polymerization of γ-benzyl-L-glutamate N-carboxyanhydride(BLG-NCA) and its subsequent deprotection of benzyl groups. The PLGA chains were cross-linked with cystamine, and thus forming a type of redox responsive drug delivery system(MSN-cPLGA). The structures were characterized by Fourier transform infrared spectrometry(FTIR), transmission electron microscopy(TEM) and energy disperse spectrometry(EDS), demonstrating that disulfide groups existed on the surfaces of MSN-cPLGA particles. The thermal gravimetric analysis(TGA) results show that the PLGA mass fraction is about 33.4% in the MSN-cPLGA hybrid. The in vitro drug release experiments showed that the MSN-cPLGA hybrid can realize the controlled release of model drugs(5-fluorouracil) in response to redox environment. Even 0.1 mmol/L dithiothreitol(DTT) can accelerate the drug release speed, and a concentration of 10.0 mmol/L DTT is higher enough to trigger the open of cross-linked PLGA network so as to realize rapid release of drugs. All the results demonstrate that the cross-linked PLGA chains on the surface of MSN could act as efficient gatekeepers to control the on-off of the pores, showing potential application in drug delivery system.

In order to realize controlled dual release of two hydrophobic drugs with distinct rates in a vehicle, novel poly(lactic-co-glycolic acid) (PLGA) composite nanofibers encapsulated with micelles were successfully fabricated by "emulsion-electrospinning." Brefeldin A (BFA) was firstly embedded in monomethoxy-poly(ethylene glycol)-b-poly(L-lactide) (MePEG-PLLA) micelles. By means of "emulsion-electrospinning," paclitaxel (PTX) and polymeric micelles contained BFA were successfully loaded into the electrospun PLGA composite nanofibers. The in vitro release results demonstrated that the location of the drugs in the electrospun fibers determined their release profiles. BFA had a long-term and sustained release while PTX had a relatively rapid release in the dual drugs delivery system. In vitro cytotoxicity studies revealed that the composite nanofibers with two drugs restrained HepG-2 cells more efficiently. These results strongly suggested that the electrospun composite nanofibers containing polymeric micelles can be used as an effective controlled dual release of hydrophobic drugs and were suitable for postoperative chemotherapy of cancers.

Novel composites based on cubic binary nickel cobaltite oxide intimately standing on nitrogen doped reduced graphene sheets (NRGO–NiCoO2) were prepared by a simple one step hydrothermal synthesis. The results showed that the highly crystalline NiCoO2 nanoparticles with a uniform size were homogeneously distributed on nitrogen-doped reduced graphene sheets (NRGO). The homogeneous composites combined NiCoO2, which has high specific capacitance, and NRGO, which has efficient electronic conductivity, to consequently yield low resistance conduction between metal oxides and graphene due to a barrier-free contact. The synergistic effect of NRGO substrates and NiCoO2 nanoparticles promoted the electrochemical performance of the composites. The electrochemical properties of NRGO–NiCoO2 can be easily tuned by altering the amount of nitrogen-composed reducer. The NRGO–NiCoO2 composites exhibited a remarkable specific capacitance of 508 F g−1 at 0.5 A g−1, an excellent rate performance in cyclic voltammetry test (from 5 to 90 mV s−1) and good galvanostatic charge–discharge measurements (from 0.5 to 20 A g−1). The capacitance was maintained at 93% of the original value even after 2000 cycles. The flexible devices were assembled, which possessed a specific capacitance of 58 F g−1 at 0.5 A g−1. This facile one-step strategy is an effective method for developing excellent supercapacitor electrodes.

A new class of thin, safe and foldable solid composite electrolytes are produced by uploading 3-arm poly-(methoxy-poly(ethylene glycol) methacrylate) (3PEG) onto three different electrospun membranes, poly(vinylidene fluoride-co-hexafluoropropylene) (P(VdF-HFP)) membrane, 3PEG co-sprayed P(VdF-HFP) membrane (3PEG/PHP) and polyethylene terephthalate membrane (PET) and are named 3PEG@PHP, 3PEG@3PEG/PHP and 3PEG@PET, respectively. The electrospun membranes serve as a skeleton to enhance the mechanical strength of composite electrolytes, whereas 3PEG filled in the micropores of the matrix affords an ion transport carrier. Among these composite electrolytes, the one based on a PET electrospun membrane exhibited a high ionic conductivity of 5.9 × 10−4 S cm−1 at 100 °C because of it possessing the lowest shrinkage rate with high filling loading of 3PEG. The decomposition potential of the composite electrolytes is above 4.5 V at 100 °C. Successful charge and discharge cycling of 3PEG@PET based all solid state lithium ion battery have maintained the initial discharge capacity of 137.6 mA h g−1 at 0.1C, which proves that they are ideal candidates for all solid state rechargeable lithium ion batteries.

ZnO has been widely investigated as important biomaterials and antibacterial materials. However, the aggregation of nanoparticles and its potential toxicity may hinder its final application. Herein, biocompatible gelatin chains were grafted on the surface of ZnO via mussel inspired method to prevent the aggregation of the ZnO nanoparticles. The in vitro test showed that the gelatin can greatly improve the biocompatibility of ZnO, while the antibacterial properties of ZnO against both E. coli and S. aureus were maintained.

A smart ZnO@PNIPAM hybrid was prepared by grafting thermal responsive poly(N-isopropylacrylamide) (PNIPAM) on zinc oxide (ZnO) nanoparticles via surface-initiated atom transfer radical polymerization (ATRP). The thermal gravimetric analysis (TGA) shows that the grafting amount of PNIPAM was about 38%, and the SEM images show that the PNIPAM chains can prevent the aggregation of ZnO nanoparticles. The responsive properties of ZnO@PNIPAM were measured by photoluminescence spectra, and the results demonstrate that the PNIPAM chains grafted on ZnO surfaces can realize reversible thermal responsive and photoluminescence properties. An anticancer drug, doxorubicin (Dox), was used as a model drug and loaded into the hybrid nanoparticles, and an in vitro drug release test implied that ZnO@PNIPAM could work as a thermal responsive drug delivery system. Furthermore, pH sensitive drug releases were carried out in acetate buffer at pH 5.0 and pH 6.0 and in water at pH7.0, and the results showed evident pH dependency, showing its pH responsive properties.

In this article, a nonenzymatic sensor based on Ni(OH)2/electroreduced graphene oxide (ERGO)-multiwalled carbon nanotube (MWNT) nanocomposites is fabricated via convenient electrodeposition of Ni(OH)2 nanoparticles on ERGO-MWNT film modified glass carbon electrode (GCE). Graphene oxide (GO) sheets can serve as surfactants to stabilize the dispersion of pristine MWNTs in aqueous solution, rendering a fine coverage of ERGO-MWNT film on GCE during the fabrication process. MWNTs perform as conducting bridges between ERGO sheets to enhance the electron transfer rate in the substrate. By combining the advantages of ERGO and MWNTs, together with electrocatalytic effect of Ni(OH)2 nanoparticles, the well-designed nanocomposites exhibit excellent sensing behavior towards glucose and hydrogen peroxide (H2O2). The linear detection ranges for glucose and H2O2 are 10-1500 µM and 10 µM-9050 µM while the detection limits are 2.7 µM and 4.0 µM, respectively. Furthermore, a very high sensitivity is achieved with 2042 µAm M(-1) cm(-2) estimated for glucose and 711 µAm M(-1) cm(-2) for H2O2. These results suggest that Ni(OH)2/ERGO-MWNT nanocomposites thus easily prepared through a green electrochemical method are promising electrode materials for biosensing. Additionally, good recoveries of analytes in real samples like urine and milk confirm the reliability of the prepared sensor in practical applications.

Multiple drugs-loaded electrospun composite nanofibrous scaffolds have attracted much interest as drug delivery vehicles for the treatment of tissue defect after tumor resection. In this study, a novel mesoporous ZnO/poly(lactic-co-glycolic acid)/gelatin (mZnO/PLGA/GE) electrospun composite fiber encapsulated with both hydrophilic drug (doxorubicin hydrochloride, DOX) and hydrophobic drug (camptothecin, CPT) is fabricated. mZnO is firstly used to encapsulate DOX. Then, the DOX-loaded mZnO (DOX@mZnO) and CPT were mixed with PLGA/GE solution to fabricate electrospun hybrid nanofibers. The in vitro release results demonstrated that the CPT in the composite fibers presented a fast release, while DOX showed a sustained release behavior. The cell cytotoxicity test indicated that the composite nanofiber with two drugs showed strong antitumor efficacy against HepG-2 cells. Moreover, the addition of GE increased the hydrophilicity of the composite fibers. More importantly, the incorporated of mZnO within the PLGA/GE nanofibers cannot only significantly reduce the burst release of DOX, but also improve the mechanical durability of the composite nanofibers. Thus, the composite nanofibers could be a versatile drug delivery system encapsulated with both hydrophilic and hydrophobic anticancer drugs as implantable scaffolds for potential postsurgical cancer treatment.

Hierarchical pore structures in the composite electrode materials can offer greater accessibility to active sites for the lithium ions, shorter ion diffusion distances and quicker lithium ion diffusion, which can enable the high-rate and high-energy Li-ion batteries (LIBs). In this work, hierarchically porous cocoon-like MnO/C composites (PCM) have been prepared using natural agaric as raw materials via a sustainable and facile method associated with the hydrothermal and annealing treatment. The as-prepared porous PCM composites show a high reversible capacity of 981 mAh g−1 at 0.1 A g−1 and remain an high discharge capacity of 640 mAh g−1 after 900 cycles at 1 A g−1. Even at the high current density of 5 A g−1, the electrode can still deliver a high capacity of 440 mAh g−1. More importantly, the high MnO content (∼78 wt %) and micron-scale structure of PCM composite greatly improve the high specific capacity and tap density of electrode materials, and help to meet the requirements for practical application. Therefore, such novel preparation strategy of composite electrode from agaric also develops a new route to fully utilize the biomass resources for high-performance LIBs and other energy storage devices.

In order to extend the application of magadiite to optical fields (rather than the usual focus on adsorption, catalysis, ion exchange, etc.), a magadiite-CdS (Mag-CdS) composite was synthesized from Na-magadiite by ion exchange. Various techniques were used to characterize the composite. X-ray diffraction results indicated that the Mag-CdS composite retained the host magadiite structure in spite of decrease in the intensity of the X-ray diffraction peak of the host magadiite. The analytical results confirmed the formation of the Mag-CdS composite, along with the modification of the optical properties of CdS by the host magadiite.

Novel biocompatible poly(lactide-co-glycolide) (PLGA) nanofiber mats with favorable biocompatibility and good mechanical strength were prepared, which could serve as an innovative type of tissue engineering scaffold or an ideal controllable drug delivery system. Both hydrophobic and hydrophilic drugs, Cefradine and 5-fluorouracil were successfully loaded into PLGA nanofiber mats by emulsion electrospinning. The natural bioactive protein gelatin (GE) was incorporated into the nanofiber mats to improve the surface properties of the materials for cell adhesion. Nanofibrous scaffolds were characterized by scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, contact angle and tensile measurements. Emulsion electrospun fibers with GE had perfect hydrophilic and good mechanical property. The in vitro release test showed thedrugs released from emulsion electrospun fibers, which achieved lower burst release. The cells cytotoxicity experiment indicated that emulsion electrospun fibers were less toxic and tended to promote fibroblasts cells attachment and proliferation, which implied that the electrospun fibers had promising potential application in tissue engineering or drug delivery.

Biodegradable poly(butylene succinate) (PBS)/single-walled carbon nanotube (SWCNT) nanocomposites were successfully prepared through silication and physical blend between PBS and acyl aminopropyltriethoxysilane functionalized single-walled carbon nanotube (SWCNT-APTES), which was obtained from acylate between 3-aminopropyltriethoxysilane and acyl chloride functionalized single-walled carbon nanotube. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) observations revealed that the PBS chains were covalently attached to the SWCNT-APTES by hydrolysis. PBS/SWCNT-APTES nanocomposites after hydrolysis exhibited strong interfacial interaction between SWCNT-APTES and PBS matrix, leading to a less agglomeration. However, the PBS/SWCNT-APTES nanocomposite prepared by only physical blend without hydrolysis exhibited severe reagglomeration of SWCNT in the PBS. The addition of SWCNT-APTES enhanced the crystallization of the PBS in the nanocomposites for both approaches of hydrolysis and physical blend due to the heterogeneous nucleation effect while the crystal structure of PBS remained. Especially, a more significant increase of crystallization rate for physical blend was present as comparison to PBS/SWCNT-APTES after hydrolysis due to the higher diffusion constant, which is attributed to the change of surface properties of nanotubes. Furthermore, the incorporation of SWCNT-APTES improved the storage modulus of the nanocomposites compared with that of neat PBS. The PBS/SWCNT-APTES nanocomposites after hydrolysis showed of higher tensile strength than PBS/SWCNT-APTES nanocomposite without hydrolysis.

A new type of polypeptide (poly(γ-benzyl-L-glutamate) (PBLG)) modified hydroxyapatite (HA)/poly(L-lactide) (PLLA) nanocomposites (PBLG- g -HA/PLLA) were prepared by the solvent-mixing method, and their mechanical and thermal properties were investigated. The tensile test showed that the mechanical properties of PBLG- g -HA/PLLA nanocomposites were better than that of PLLA, even a 0.3 wt% content of PBLG- g -HA in the nanocomposites could make the tensile strength 12% higher than that of the neat PLLA sample, and the tensile modulus was about 17% higher than that of the PLLA sample. The thermal gravimetric analysis (TGA) showed that the PBLG- g -HA/PLLA composites have better thermal stability than the PLLA sample. The differential scanning calorimetry (DSC) was used to characterize the effect of PBLG- g -HA on the crystallization of PLLA. The isothermal crystallization behavior showed that the half crystallization time (t1/2) of PBLG- g -HA/PLLA was much shorter than that of the PLLA sample. When the PBLG- g -HA content was 10%, t1/2 was only 18.7 min, while t1/2 of the PLLA sample was 61.4 min. The results showed that the PBLG- g -HA worked as a nucleating agent and enhanced the crystallization speed of PLLA.

Hydroxyapatite/poly(L-lactide) (HA/PLLA) nanocomposites were prepared by the solvent mixing method. The isothermal crystallization behavior was studied by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The results show that the crystallization behavior of HA/PLLA composites was strongly affected by the content of HA and crystallization temperature, and the addition of HA could promote nucleation and enhance the crystallization rate. When isothermal crystallization was carried out at 110°C, the HA/PLLA nanocomposite with 1% HA content crystallized most rapidly among all the composites and the half crystallization time was only 1.0 min. Banded spherulites were observed for the HA/PLLA composites, but no banded spherulites were seen in the crystals of PLLA under the same condition.

Hydroxyapatite (HA) nanoparticles grafted by poly(N-isopropylacrylamide) (PNIPAM) brushes (PNIPAM-g-HA) have been synthesized by the surface-initiated atom transfer radical polymerization (ATRP) of N-isopropylacrylamide (NIPAM). The surface grafting amount of PNIPAM ranges from 15.5% to 46.4%. PNIPAM-g-HA has been characterized by FT-IR spectroscopy, thermal gravimetric analysis, X-ray diffraction, and scanning electron microscopy (SEM). The UV transmittance spectra and the particle size analysis of PNIPAM-g-HA in aqueous solution demonstrates that the PNIPAM-g-HA possess reversible thermal stimuli responsive properties. An in vitro bioactivity assessment indicates that PNIPAM-g-HA can induce the mineralization of Ca(2+) and HPO(4) (2-) and possesses an excellent bioactivity. The cell culture results show that the cells adhered to the surface of PNIPAM-g-HA grow better than on HA, and the area of the cells on the surface of PNIPAM-g-HA is much greater than for HA, which proves that the PNIPAM-g-HA has a better biocompatibility than HA.