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As the most commonly used additive manufacturing technology, fused deposition modeling (FDM) still faces some technical issues caused by temperature change-induced unsteady thermal stress and warpi...

Flexible aqueous battery is considered to be one of the most promising energy storage devices for powering flexible electronics. However, inferior interfacial compatibility in electrode–electrolyte interfaces and inefficient ionic channel of electrolytes usually result in potential troubles when applied in practical applications. Herein, we report a mild synthetic route to a sodium lignosulfonate-polyacrylamide hydrogel electrolyte with a high adhesiveness to achieve low electrode–electrolyte interfacial resistance and fast ionic conduction. Comprehensive experiments show that the catechol groups from sodium lignosulfonate demonstrate strong interactions with both cathode and anode materials, and thus greatly reduce the contact resistances across the electrodes. Meanwhile, the existence of sulfonate groups significantly enhances the ionic conductivity of the hydrogel electrolyte. Benefiting from this design, a low ohmic resistance of 3.8 Ω (i.e., 11.4 Ω cm2 ), a low charge transfer resistance of 22.5 Ω (i.e., 67.5 Ω cm2 ), a high ionic conductivity of 31.1 mS cm−1 as well as a 100% capacity retention upon harsh bending deformation can be realized in the flexible zinc ion battery, which are significantly superior to those in the traditional candidates. The present investigation provides new insight into addressing the interfacial issue plaguing flexible energy storage devices.

In this work, a functionalized polycaprolactone (PCL) composite fiber combining calf-type I collagen (CO) and natural drug usnic acid (UA) was prepared, in which UA was used as an antibacterial agent. Through 3D near-field electrospinning, the mixed solution was prepared into PCL/CO/UA composite fibers (PCUCF), which has a well-defined perfect arrangement structure. The influence of electrospinning process parameters on fiber diameter was investigated, the optimal electrospinning parameters were determined, and the electric field simulation was conducted to verify the optimal parameters. The addition of 20% collagen made the composite fiber have good hydrophilicity and water absorption property. In the presence of PCUCF, 1% UA content significantly inhibited the growth rate of Gram-positive and negative bacteria in the plate culture. The AC-PCUCF (after crosslinking PCUCF) prepared by crosslinking collagen with genipin showed stronger mechanical properties, water absorption property, thermal stability, and drug release performance. Cell proliferation experiments showed that PCUCF and AC-PCUCF had no cytotoxicity and could promote cell proliferation and adhesion. The results show that PCL/CO/UA composite fiber has potential application prospects in biomedical dressing.

A novel nanocellulose - microcrystalline cellulose complex (NCMC) with special hierarchical structure has been prepared by grafting nanocellulose (NC) onto the surface of microcrystalline cellulose (MCC) via different silane coupling agents in this paper. The cellulose complex was easier to separate and purify from the solution in the preparation process than nanocellulose due to its large size, and was used to reinforce polylactic acid (PLA) as 3D printing materials through a melt-blending process. The results showed that NCMCs prepared by different silane coupling agents had different surface morphologies. Nanocelluloses formed a network structure on the surface of KH-550 treated NCMC, while a spherical structure wrapped by nanocellulose was formed on the surface of KH-560 treated NCMC, and KH-570 treated NCMC was the nanocellulose network with a small amount of irregular silica impurities. The mechanical properties, crystallinity of polymer and thermal stability of NCMC/PLA composites are obviously improved by adding a small amount of NCMC. Compared to pure PLA, the tensile strength, bending strength and elongation at break of the NCMC/PLA composites were increased by 40.3%, 84.1% and 34.3%, respectively. It is because NCMC had higher specific surface area and more complex surface structure than MCC, that led to more thorough grafting reaction on polylactic acid during high temperature extrusion blending process. The DSC results also showed that a small amount of NCMC could promote the crystallization of PLA as 3D printing materials. Besides, NCMC/PLA composites did not block the printing nozzle in continuous 3D printing, and the printed products had better appearances. The obtained materials are environmentally friendly, renewable and ideal for 3D printing.

Step-scheme (S-scheme) photocatalysts have been proposed for highly efficient charge separation and strong redox activity in the photocatalysis field. Here, we reported a facile strategy to obtain the S-scheme heterojunction composite TiO2/chlorophyll (Chl). The S-scheme heterojunction enables the significant improvement of electron transfer efficiency at the interfacial heterojunction of TiO2/Chl. Also, the lifted conduction band and valence band of TiO2/Chl resulted in more than 1.61 times generation of reactive oxidizing species, compared to that of bare TiO2. In addition, TiO2/Chl was applied as a photocatalytic bactericidal material to fabricate commercial masks for prolonged life span of the mask. The TiO2/Chl-coated mask filter exhibited excellent bactericidal effect on Escherichia coli under light illumination (2.94 × 107 cfu E. coli were killed by 1 cm-2 coated mask filters within illumination of 3 h), while commercial mask filters showed no bactericidal effect. After three circulation-sterilization tests, the TiO2/Chl-made mask filter maintained the initial bactericidal effect, which greatly extended the life span of the mask that presents a promising strategy to alleviate the supply stress of masks.

Biocompatible and bioactive scaffolds with multiscale porosity, shape memory effect and drug delivery performance are highly promising in bone tissue engineering applications within the approach of minimally invasive surgical implantation. In this study, we report an effective method to fabricate multiscale porous bioactive (MPB) scaffolds with shape memory effect by freeze drying of 3D printed high internal phase Pickering emulsion (Pickering HIPE) templates stabilized by hydrophobically modified hydroxyapatite and silica nanoparticles. MPB scaffolds containing a shape memory polymer matrix of poly(D,L-lactide-co-trimethylene carbonate) display high porosity and fully interconnected filament networks with multiscale pore structures. The in vitro biomineralization study verifies that MPB scaffolds are bioactive with the apatite formation ability. The thermal property testing shows that the glass transition temperature of MPB scaffolds is easily tuned to fall between 45.9 and 49.1 °C by varying the HIPE composition. Moreover, MPB scaffolds exhibit observable shape memory properties with fast shape recovery. The antibacterial drug enrofloxacin can be efficiently loaded into MPB scaffolds and then released in a sustained manner displaying effective antimicrobial effect. Furthermore, cell culture assays confirm that MPB scaffolds could sustain the cell growth, proliferation and osteogenic differentiation, indicating the cytocompatibility and osteoinduction activity of MPB scaffolds. Therefore, combining freeze drying with 3D printing of Pickering HIPE templates paves the way towards MPB scaffolds with shape memory effect, which are promising as minimally invasive implantation scaffolds in bone tissue engineering applications.

To promote natural waste resource utilization, a novel biocomposite, composed of waste crab shells and poly (lactic acid) matrix, was developed by combining chemical treatment and 3D printing. A crab shell powder (ISCSP) with an abundant porous structure and a high specific surface area was obtained by treatment with hydrochloric acid and sodium hydroxide. Importantly, under the optimal printing parameters determined by the finite element analysis, test samples, and porous bones were successfully printed using CSP/PLA composites by a commercial fused deposition modeling (FDM) 3D printer. The morphology, mechanical and thermal properties, antibacterial properties, and biocompatibility of the CSP/PLA composites were then assessed. Our results revealed that the tensile strength and flexural strength of the ISCSP/PLA composites reached 58.71 and 90.11 MPa, which were 28.6 % and 28.8 % higher than that of pure PLA, respectively. The glass transition and melting temperatures of the composites remained similar to those of pure PLA. Interestingly, the addition of CSP increased PLA crystallinity, which could be attributed to the nucleation effect of CSP in the system. The antibacterial activity of the PLA-1.5ESCSP composite samples against Escherichia coli (E. coli) was greater than 99 %. More importantly, the live/dead assay showed that the CSP/PLA composites possessed excellent biocompatibility. Therefore, the developed CSP/PLA biocomposites are potential feedstocks for 3D printing in bone tissue engineering and may be used as graft substitutes in reparative and reconstructive surgery. They are especially beneficial due to their superior mechanical and thermal properties, excellent antibacterial activities, and significant biocompatibility.

Bioactive and biocompatible scaffolds possessing hierarchical porous structures and tunable multi-functional performance have attracted increasing interest in the biomedical field, especially in bone tissue engineering. In this work, we report a convenient and effective approach to construct bioactive nanoparticle/poly(ε-caprolactone) (BNPCL) scaffolds with hierarchical porous structures based on solvent evaporation of 3D printed water-in-oil high internal phase emulsion (HIPE) templates, containing hydrophobically modified hydroxyapatite and silica nanoparticles in the oil phase. The hierarchical porous structures consist of mm-scale macropores formed by 3D printing and μm-scale micropores from HIPE templates. The micropore structures and mechanical properties of BNPCL scaffolds are easily tailored by varying the preparation conditions of the HIPE templates. An in vitro biomineralization study shows that BNPCL scaffolds possess excellent bioactivity because of effective formation of apatite particles on them. Moreover, the in vitro drug release studies using ibuprofen display the potential of BNPCL scaffolds as drug carriers. Furthermore, cell culture assays prove that BNPCL scaffolds have good cytocompatibility to effectively support cell adhesion, growth and proliferation. All the results imply that combining solvent evaporation with 3D printing of HIPE templates is a promising alternative approach to fabricate hierarchical porous scaffolds for bone tissue engineering applications.

Cancer is one of the most concerned diseases in the world, where there is still no reported specifically targeted drugs with high effect. In this study, mesoporous silica with a large pore size of 25.25 nm and magnetic cores was prepared as a carrier of doxorubicin for anti-cancer drug delivery. Besides its superior biocompatibility properties and functional surface, the large mesopores provided enough space for multiple chemical modification and in-situ growth of Au nanoparticles. Amino groups were grafted on the inner mesopores to capture the drug molecules via complexation. Cooperated with the steric hindrance of β-Cyclodextrin (β-CD) on the external surface, a perfect response to acid environment was established. Meanwhile, the presence of magnetic cores and Au nanoparticles gave the system sensitive response to both alternating magnetic field (AMF) and near infrared ray (NIR). What’s more, the combination of magnetic cores and Au nanoparticles provided a strong medical nuclear magnetic resonance (NMR) signal with a linear correlation of 0.9946. The accurate dose related NMR signal and the multi-stimuli sensitive response, including pH, AMF and NIR, make this system immense potential for imaging diagnosis and targeted drug delivery therapy.

Public health safety issues have been plaguing the world since the pandemic outbreak of coronavirus disease (COVID-19). However, most personal protective equipments (PPE) do not have antibacterial and anti- toxicity effects. In this work, we designed and prepared a reusable, antibacterial and anti-toxicity Polyacrylonitrile (PAN) based nanofibrous membrane cooperated with Ag/g-C

Fluid bath-assisted three-dimensional (3D) printing is an innovative 3D printing strategy that extrudes liquid ink materials into a fluid bath to form various 3D configurations. Since the support bath can provide in situ support, extruded filaments are able to freely construct complex 3D structures. Meanwhile, the supporting function of the fluid bath decreases the dependence of the ink material's cross-linkability, thus broadening the material selections for biomedical applications. Fluid bath-assisted 3D printing can be divided into two subcategories: embedded 3D printing and support bath-enabled 3D printing. This review will introduce and discuss three main manufacturing processes, or stages, for these two strategies. The stages that will be discussed include preprinting, printing, and postprinting. In the preprinting stage, representative fluid bath materials are introduced and the bath material preparation methods are also discussed. In addition, the design criteria of fluid bath materials including biocompatibility, rheological properties, physical/chemical stability, hydrophilicity/hydrophobicity, and other properties are proposed in order to guide the selection and design of future fluid bath materials. For the printing stage, some key technical issues discussed in this review include filament formation mechanisms in a fluid bath, effects of nozzle movement on printed structures, and design strategies for printing paths. In the postprinting stage, some commonly used postprinting processes are introduced. Finally, representative biomedical applications of fluid bath-assisted 3D printing, such as standalone organoids/tissues, biomedical microfluidic devices, and wearable and bionic devices, are summarized and presented.

Background: The prevention and treatment of dairy cow mastitis during the dry period are crucial for the dairy industry. In this work, 200 dairy cows without mastitis and normal entering dry period were selected and randomly divided into 4 groups, for the first time, to explore the prevention effects using the different formulations of Cefquinome Sulfate Breast Injection with varied excipients. Methods: Three formulations with various excipients were further evaluated based on the drug residue analysis, somatic cell reduction in the milk and clinical symptoms of mastitis. In the control group, cloxacillin benzathine was utilized for comparisons. Result: All three Cefquinome test groups showed a better effect on prevention than the benzathine cloxacillin group in terms of drug release time, post-partum drug residue, reducing somatic cell count and preventing mastitis in the dry period. Various excipients showed slightly different impacts on the drug residues, the changes in somatic cell counts of dairy cows before and after medication. The prevention effects on mastitis from different excipients were similar after 30 d.

Step-scheme (S-scheme) photocatalysts have been proposed for highly efficient charge separation and strong redox activity in the photocatalysis field. Here, we reported a facile strategy to obtain the S-scheme heterojunction composite TiO

Carbon-coated Cu-TiO2 nanocomposite (Cu-TiO2@C) was constructed using one-step method of thermal reduction. Their photocatalytic activity for hydrogen production from methanol aqueous solution was investigated. Under UV–vis light irradiation, the hydrogen yield of the 10 mg optimal Cu-TiO2@C reached 269.1 μmol h−1, which was very close to that of Pt@TiO2 (290.8 μmol h−1). The Cu-TiO2@C also displayed much higher photocatalytic stability in comparison with Cu-TiO2 without coated carbon layer. The nano-Cu as photocatalytic active site improve the efficiency of photoinduced carrier separation. The carbon layer with the ability to transfer photogenerated electrons faster and to adsorb hydroxyl radicals more easily, leading to a very significant increase the reaction rate. In addition, the carbon layer can also provide a chemical protection to the Cu nanoparticles and increase the stability of the photocatalysts. The Cu-TiO2@C photocatalyst with the low cost, enhanced photostability and photocatalytic activity is expected to be an excellent nanocomposite t in reforming of biomass or bio-derivatives field.

Surface functionalization of nanomaterials has been realized to be vital to fabricate drug delivery nanosystems that offer high drug loading and sustained release with remarkable in vivo biocompatibility and bioavailability. From these systems, nanomaterials such as titania nanotubes (TNTs) can be functionalized and designed as specific drug delivery nanosystems. Here, two kinds of novel drug delivery nanosystems, i.e. Enro-NH2-TNTs and Enro-SH-TNTs, were first prepared by combining the characteristic pH adjusted enrofloxacin (Enro) recrystallized loading process and surface silane coupling agent modified titania nanotubes (NH2-TNTs and SH-TNTs). FTIR analysis exhibited that Enro molecules interacted with surface grafted groups, such as –NH2 or –SH, through an electrostatic effect or a hydrogen effect. The recrystallization and loading of Enro molecules into the two types of modified TNTs was identified using X-ray diffraction patterns (XRD), surface area analysis (BET), and transmission electron microscopy (TEM). In vitro experiments exhibited excellent controlled-release properties and further proved that the Enro drugs had been loaded into TiO2 nanotubes, which were influenced by grafted molecules. In vitro cell viability, hemolysis assays and cell apoptosis experiments showed that surface modification could increase the biocompatibility and lower the cytotoxicity of TNT nanomaterials to cells. These modified drug delivery nanosystems afforded higher drug bioavailability and longer drug effects on in vivo administration to chickens. Surface modification combined with a pH adjusted process has a large potential for fabricating long-acting drug delivery nanosystems, especially with hydrochloride drugs.

A CdS sensitized hydrogenated TiO2 nanorod arrays (CdS@HTNRs) film was developed for the selective visible-light-driven photoelectrochemical (PEC) sensing of Cu2+ ion. The sensitive determination was based on extremely high PEC activity of the as-prepared CdS@HTNRs, i.e, the photocurrent density of the as-prepared CdS@HTNRs electrode could reach up to 10.1 mA cm−2, which was 33.7 times higher than that of the pure HTNRs film. Dramatic photocurrent quenching was observed upon immersion of the CdS@HTNRs electrode into Cu2+ solution. The analytical principle is based on significant quenching of photocurrent, i.e, the formation of CuS and subsequent CuxS (x = 1, 2) produced on the electrode surface under illumination reduces the absorption of light and boosts the electron-hole recombination, respectively. Due to the large photocurrent density of the as-prepared CdS@HTNRs and the high selectivity of chemical recognition reaction between CdS and Cu2+, the photocurrent quenching of CuxS, is proposed to be sensitive and selective in detecting Cu2+ ion. The linear detection range could be 0.8 nM to 82.0 μM with the detection limit of 0.3 nM via controlling recognition reaction time to be 7 min. The sensor was also successfully applied in the detecting Cu2+ ion in real samples such as tap water, lake water and urine.

Biocompatible porous scaffolds with tunable microstructures and drug delivery ability have aroused increasing attention in the application of the biomedical fields, especially in tissue engineering. In this study, we have facilely fabricated the poly(l-lactic acid)-modified halloysite nanotubes (m-HNTs)/poly(e-caprolactone) (PCL) porous scaffolds by direct solvent evaporation of m-HNTs stabilized water in oil Pickering emulsion templates, which contain PCL in the oil phase. The obtained scaffolds have possessed the porous microstructures, which can be easily tailored by varying the preparation conditions of emulsion templates including m-HNTs concentrations and the volume ratios of water to oil. Furthermore, the antibacterial drug enrofloxacin (ENR) has been loaded into the scaffolds, and the in vitro release studies show the potential of m-HNTs/PCL porous scaffolds as drug carriers. And the antimicrobial test results have proved that the ENR-loaded porous scaffolds exhibit obvious and long-term antibacterial activity against Escherichia coli. In addition, mouse bone mesenchymal stem cells (mBMSCs) are cultured on the m-HNTs/PCL porous scaffolds, and the results of cell counting kit-8 assay and confocal laser scanning microscope observation show that the m-HNTs/PCL porous scaffolds are cytocompatible, because mBMSCs can attach, develop and proliferate well on the porous scaffolds. All the results indicate that the m-HNTs/PCL porous scaffolds hold great potential applications in tissue engineering as scaffolds and/or drug carriers.

Cinnamon oil (CMO) has a wide variety of promising applications due to its multifunctional activity, especially excellent antibacterial activity. However, CMO is highly unstable and volatile, which clearly limit its application fields. In this work, CMO is encapsulated in composite emulsion hydrogels to solve the above issue. The CMO-loaded composite emulsion hydrogels are facilely and effectively fabricated by free radical polymerization of acrylamide in the continuous phase of oil-in-water concentrated emulsion templates. Gelatin serves as the effective polymer emulsifier to prepare the CMO-in-water concentrated emulsions. The study results display that the CMO can be effectively loaded into the hydrogel matrix. And the microstructure and mechanical properties of the composite hydrogels can be easily tuned by changing internal phase fraction of the concentrated emulsion templates. Increasing internal phase fraction leads to the increase of pore sizes and the decrease of the Young’s modulus and compressive stress. Moreover, the release studies indicate that the CMO-loaded composite hydrogels display the sustained CMO release profiles. Furthermore, the antibacterial assays verify that the CMO-loaded composite hydrogels demonstrate an excellent and long-term antibacterial activity against Staphylococcus aureus and Escherichia coli. All the results indicate that the CMO-loaded composite emulsion hydrogels prepared in this study can be applied as promising long-term antibacterial materials. Free radical polymerization based on concentrated emulsion templates is a promising alternative approach to fabricate antibacterial essential oil-loaded composite emulsion hydrogels, which could be acted as antibacterial materials.

Mesoporous coralloid NaInO2 was prepared through a facile secondary calcination reaction based on mesoporous In2O3. As a binary sodium transition metal oxide containing a layered structure, the application of prepared mesoporous NaInO2 for HCHO oxidation at room temperature was investigated in this study. After 1.0 wt% Pt supported, the sample possessed a high initial removal efficiencies of HCHO up to 91.4% in 15 min, as well as low final residues of less than 5.5 ppm in 60 min. The characterizations indicate that prepared mesoporous NaInO2 has abundant interface structural defects (XRD peak shifting) and substantial BET surface area of 51.9 m2/g, which may generate surface oxygen vacancies manifesting as large amounts of chemisorbed oxygen (OC/Ototal as 36.09%). According to the research results, surface oxygen vacancies might help greatly to capture gaseous HCHO molecules, where chemisorbed oxygen being a cofactor for HCHO oxidation, and then the catalyst transformed HCHO into formate, carbonate and finally CO2 indicated by in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS) analysis. Overall, this study provided a promising way for designing Pt-supported catalysts for ambient air purification by introducing surface defects (oxygen vacancies) and chemisorbed oxygens.

Flexible lithium ion batteries (LIBs) have been recognized as indispensable energy storage devices compatible with the emerging flexible/stretchable wearable electronics. Herein, we design a three-dimensional (3D) hierarchical Fe2O3@CNFs@MoS2 fabric film as a self-standing and robust anode, in which ultrathin curly MoS2 nanosheets are tightly anchored onto the surface of an interconnected Fe2O3@carbon nanofiber (CNF) substrate. The flexible Fe2O3@CNFs fabric electrode can establish a 3D continuous conducting network and maintain superior structural integrity, while the unique hierarchical MoS2 nanosheets can further shorten the Li+ diffusion path, expand the interfacial contact and offer increased active sites for reversible lithium insertion/extraction reactions. The as-prepared hierarchical Fe2O3@CNFs@MoS2 fabric is directly used as a film anode for LIB half-cells, which exhibits an excellent reversible capacity of 938 mA h g−1 at 0.2 A g−1 after 300 cycles and high rate capabilities of 304 mA h g−1 at 5.0 A g−1. When combined with a LiCoO2 (LCO) cathode and PVDF/PPC gel polymer electrolyte, the Fe2O3@CNFs@MoS2 fabric-based quasi-solid-state flexible full cell realizes outstanding capacity performance and mechanical flexibility. It delivers an ultrahigh areal specific capacity of ≈6.47 mA h cm−2, superior cycling tolerance and a high capacity retention of 90.8% after 300 cycles even in the 90° bending position, which are among those of the so far reported best-performing flexible LIBs. Along with a simple and eco-friendly fabrication process, this 3D nanoarchitectured Fe2O3@CNFs@MoS2 fabric could provide a promising avenue toward high performance flexible LIBs and other rechargeable batteries.

The super stretchability, ultrahigh toughness, good self-recovery and shape memory performance are very important for the practical application of hydrogels. However, most of hydrogels do not demonstrate the above-mentioned features at the same time. In this study, we develop a promising and versatile strategy for the synthesis of novel tough poly(acrylamide-co-acrylic acid)-carbon dot-ferric ion (PAmAc-Cdot-Fe3+) nanocomposite (NC) hydrogel with a dual cross-linked network, which is triggered by carbon dots (C-dots) and Fe3+ ions as physical cross-linkers. The introduction of Fe3+ ions into the first C-dot cross-linked hydrogel can form strong coordinate bonds with COO− groups of PAmAc chains and C-dots, and obviously increase the mechanical properties of hydrogels. Varying C-dot content, Ac content, or immersing time in FeCl3 solution can facilely adjust the mechanical properties of hydrogels. At optimal conditions, the PAmAc-Cdot-Fe3+ NC hydrogel displays extremely balanced and high mechanical properties (the fracture strain of 2663%, fracture stress of 4.00 MPa and toughness of 71.30 MJ/m3), good self-recovery capacity (ca. 80.5% toughness recovery after 4 h of resting) and fatigue resistance. Basing on the dynamic and reversible nature of coordination bonds, the PAmAc-Cdot-Fe3+ hydrogel also shows the stimulation-triggered shape memory performance. All the above results indicate that the introduction of strong coordinate bonds into NC hydrogel is a promising alternative method to fabricate dual cross-linked NC hydrogels with excellent comprehensive properties and functions, which have potential applications in load-bearing soft devices and soft actuators.

Porous anatase TiO 2 films with disparate submicron/nanoscale topographies were fabricated in this study. The wettability of the films could be regulated from super-hydrophilicity to hydrophobicity using a facile soft template route. The surface morphologies of the prepared films were investigated by FESEM and AFM, with the porous structures characterized via BET. The wetting property of the films with micro level morphology was studied by contact angle (CA) measurements. On the above basis, the macroporous surfaces (templated by triblock copolymer P123 or cetyltrimethylammonium tosylate (CTATos)) with superhydrophilicity (CA = 0°) and the mesoporous surface (templated by cetyltrimethyl ammonium bromide (CTAB)) with hydrophobic characteristic (CA = 96°) were detected. It is interesting to find that even though the chemical composition is hydrophilic, the hydrophobic surface could still be formed by the mesoporous topography with a possible wetting mechanism based on the Cassie model. Moreover, the morphology dominant hydrophobicity was well maintained after heating at 500 °C for 2 h (CA = 91°), bringing the material greater potential under harsh conditions.

Orientation-induced crystallization is a widely applied method of forming crystal with highly oriented structure. Here, we reported a promising matrix for orientation-induced crystallization–carbon dots (CDs), who exhibited high lattice-matching with Cu crystal. First, CDs induce self-assembly of Cu nanoparticles through organics-inorganics interface interaction, forming self-assembled mesocrystal and single crystal with large size. Second, the CDs selectively deposit on Cu {111} plane via lattice-matching, endowing Cu self-assemblies with tunable morphology including sphere, truncated octahedron, octahedron, concave octahedron and hexpods. Third, CDs also protect Cu self-assemblies from oxidation and act as efficient interface for optical conversion and electron transfer. So using as surface-enhanced Raman scattering (SERS) substrate for the first time, the CDs-coating hexpods Cu mesocrystal require no post processing and exhibit high stability and surface-enhanced Raman scattering (SERS) activity which ordinary Cu nanostructure cannot achieve.

In this study, novel bi-functional Fe 3 O 4 /mesoporous silica core/shell nanoparticles (FMSNs) modified by thiol groups ( SH) on their outer surfaces have been successfully synthesized through outside-in functionalization process, and then can be served as the three-dimensional porous supporting materials to complex with platinum ions in the mesoporous channels, where high-density amino groups ( NH 2 ) are grafted as the binding sites for chelating metal precursors in the inner of mesopores. Highly dispersed Pt nanoparticles are facilely generated and immobilized into the channel surfaces of FMSNs by an in-situ reduction using NaBH 4 as the reducing agent. The special FMSNs possess high Pt loading capacity (~ 10.38%), and can be acted as active heterogeneous catalysts for the reduction of toxic Cr(VI) to Cr(III) by using formic acid as the model reducing agent. The Pt-loaded FMSN catalysts can be facilely separated and collected by applying an outer magnetic field, and the catalysts can be reused for five times successively with excellent performance. We believe that the composites have large potential in the removal of Cr(VI) contamination from industrial waste-water in the future.

Luminescent 3D printing materials have attracted many attentions due to their promising applications of luminescent inks, hydrogels and microstructures. However, no reports have shown the priority of their fluorescence for detection of the quality of 3D printing products. In this work, novel luminescent poly (lactic acid) (PLA) composite filaments with typical aggregation-induced emission (AIE) building block (tetraphenylethene, TPE) for 3D printing have been successfully developed, by simple solution premixing and melt extrusion methods. It was found that TPE uniformly dispersed in the PLA matrix and significantly increased the crystallinity of PLA, which not only maintained the good thermal property but also improved the mechanical properties of TPE/PLA composites. Notably, the composite filaments emitted ultra-bright blue light under UV lamp, and the fluorescence intensity increased as the content of TPE increased. Finally, several brightly luminescent exquisite articles could be manufactured by a single-nozzle 3D printer with these new fluorescent filaments. Most interestingly, a thin layer of 0.4 mm TPE/PLA was implanted in the strip-shaped specimens by a dual-nozzle printer, which could be used as a very sensitively fluorescent visual inspection of the quality of 3D printing products, including the degree of bending damage and their small defects. Therefore, the development of novel luminescent TPE/PLA composites combined with 3D printing technology in this work provides a unique opportunity for the design and application of luminescent 3D printing materials.

In the present work, polylactic acid (PLA) microcapsules as novel drug delivery systems were successfully fabricated by one-step processing using an electrospray technique. Curcumin (Cur) was chosen as model drug with satisfactory loading capacity (LC%) and entrapment efficiency (EE%) greater than 95%. By judiciously adjusting spinning solvents, flow rates, polymer and drug concentrations, the monodisperse and spherical structures of Cur/PLA microcapsules observed using scanning electron microscopy (SEM) and optical microscopy were successfully generated with diameter distribution ranging from 3.8 μm to 4.4 μm. The physical-chemical characterization including, FTIR, XRD, TG, and DTA, are explored and in vitro release profiles described by Ritger–Peppas models were also investigated, showing sustained release for 200 h after a burst release in the initial 12 h. The drug-loaded microcapsules showed excellent anti-bacterial activities towards Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by using both disk diffusion and minimal inhibitory concentration methods. The anti-oxidant performance was also evaluated by using DPPH assays. In vitro cell tests, including Cell Counting Kit-8, hemolysis experiments, and cell adhesion revealed that PLA-based microcapsules had significant biocompatibility and low cytotoxicity. The study showed that the PLA-based electrospray strategy combined with spherical microcapsules has the potential for a broad range of applications in medical fields, especially in drug delivery.

Uniform TiO2/SiO2 nanospheres of 500 nm size were in situ fabricated on substrates by a facile soft templating route. The morphologies of the nanospheres on the substrates, as well as the intermediates, were evaluated by FESEM. During the synthesis, a micelle formation process transforming from rod-like micelles to vesicles to lamellar phases was proposed, attributed to the electrostatic self-assembly process of the oppositely charged cationic cetyltrimethyl-ammonium tosylate (CTATos) and anionic Si–OH in the solution. The processed substrates are transparent and super-hydrophilic with good antifogging properties. The homogeneous growth, firm substrate combination, and facile procedures are significantly advantageous for the fabrication method and can be explored with other substrates such as modified electrodes and nanoscale devices for diverse applications.

A new class of hybrid support is prepared by chemical vapor deposition of acetylene yielding carbon nanofibers (CNFs) on electrolessly plated Ni3P on carbon nanotubes (Ni3P/CNT). The as-prepared Ni3P/CNT–CNF hybrid is used to support platinum nanoparticles, produced by the microwave-assisted ethylene glycol reduction method, as an electrocatalyst (Pt/Ni3P/CNT–CNF). The as-prepared Ni3P/CNT–CNF hybrid and Pt/Ni3P/CNT–CNF catalyst are characterized by SEM, TEM, XRD, and thermogravimetric analysis. Electrochemical evaluations of the electrocatalyst are performed for methanol oxidation and oxygen reduction reactions. The electrochemical active surface area of Pt/Ni3P/CNT–CNF, evaluated both by hydrogen adsorption cyclic voltammetry (CV; 95 m2 g−1) and CO anodic stripping CV (106 m2 g−1), is higher than that of a Pt/CNT benchmark. Electrochemical evaluation of methanol oxidation and oxygen reduction reactions indicate that as-prepared Pt/Ni3P/CNT–CNF shows enhanced activity relative to that of commercial Pt/C-JM and Pt/CNT. The superior performance of as-prepared Pt/Ni3P/CNT–CNF is mostly attributed to the improved electron transfer and facilitated mass transport originating from the tailor-made Ni3P/CNT–CNF hybrid support.

Aimed at high Pt utilization efficiency and stability, Pt/TiO 2 @Ru-C electrocatalysts have been prepared by a two-stage modified polyol process, in which ruthenium nanoparticles are dotted on TiO 2 nano-bricks to form TiO 2 @Ru in the first stage, followed by deposition of platinum nanoparticles on either the in-situ formed TiO 2 @Ru or carbon black in the second stage. The electrocatalysts have been characterized by Transmission Electron Microscopy, X-ray Diffraction and Thermogravimetric analysis. The electrochemical surface area of the Pt/TiO 2 @Ru-C is 82.9 m 2 g −1 and remains to as high as 44.8 m 2 g −1 in an accelerated stability test. Catalytic activity towards methanol oxidation reaction of the catalyst in 0.5 M CH 3 OH + 0.5 M H 2 SO 4 at room temperature is found to be 487 A g −1 . TiO 2 nano-bricks are wedged in between the interfaces of carbon particles creating interpenetrated TiO 2 -Pt-C network, making them easily accessible to fuel cell reactions. Meanwhile, the interpenetrated TiO 2 prevent the electrocatalyst from agglomeration, leading to high Pt efficiency as well as durability.

Homogeneous p-type cobalt (II) oxide (CoO) nanoparticles were successfully deposited on n-type three-dimensional branched TiO2 nanorod arrays (3D-TiO2) through photochemical deposition and thermal decomposition to form a novel CoO/3D-TiO2 p-n heterojunction nanocomposite. Due to the narrow band gap of CoO nanoparticles (~2.4 eV), the as-synthesized CoO/3D-TiO2 exhibited an excellent visible light absorption. The amounts of deposited CoO nanoparticles obviously influence the hydrogen production rate in the photoelectrochemical (PEC) water splitting. The as-synthesized CoO/3D-TiO2-5 obtains the highest PEC hydrogen production rate of 0.54 mL h−1 cm−2 after five-time CoO deposition cycles (at a potential of 0.0 V vs Ag/AgCl). The photocurrent density of CoO/3D-TiO2-5 is 1.68 mA cm−1, which is ca. 2.5 times greater than that of pure 3D-TiO2. The results showed that the formation of internal electrical-field between the CoO/3D-TiO2 heterojunction, which has a direction from n-type TiO2 to p-type CoO, facilitated the charge separation and transfer and resulted in a high efficiency and stable PEC activity.

Two types of aggregation−induced emission (AIE) stereolithography resins have been prepared. The AIE thermoset photocurable resin is made by covalently crosslinking of tetrakis (4–aminophenyl) ethene, bisphenol F epoxy resin (BPF) and methylacrylic acid (MAA). However, the AIE thermoplastic photocurable resin with “OFF–ON” fluorescence response is prepared by doping the AIE luminogens to the polymers rather than covalently crosslinking. The 3D printing process of these photopolymers can be continuously monitored according to the change of the fluorescence intensity for the first time. Before printing, the solution is non−fluorescent, during the printing process, fluorescence appears because aggregation of AIE moieties, and the printed objects are highly fluorescent after photosetting. So, this work offers an important tool for measuring printing and photo−curing processes. Furthermore, the colorful models can be obtained by mixing and curing them in different proportions just like mixing pigments and the fluorescence has also been found sensitive to the phase transitions (e.g., glass transition temperature, Tg) of materials. Finally, the curing process of the prepared AIE stereolithography resins is helpful to understand the AIE mechanism and have a potential to expand the application of the AIE molecules.