Search

[Display omitted] • LZO-modified NCM811 is prepared via sol–gel coating and annealing methods. • Influence of annealing temperatures systematically studied. • The 750 °C annealed sample shows best electrochemical performances. • Optimized annealing procedure enhances microstructural stability and alleviates cation mixing. Li 2 ZrO 3 (LZO) coating has been routinely applied on Ni-rich NCM cathode materials via two-step processes to improve their electrochemical performances, but procedures for sample preparation remain elusive. Ni-rich NCM materials are particularly sensitive to temperatures, but annealing temperatures show random variation between 400 and 850 °C in literatures. In this work, the influence of annealing temperature on microstructures and electrochemical properties are systematically studied for the LZO-modified NCM811. It is found that, a thicker LZO coating with amorphous features can be obtained at a lower annealing temperature; but the LZO is fully dissolved into the crystal lattice of NCM811 at a higher temperature. The best electrochemical performance is achieved at the condition of 750 °C, because an optimized annealing temperature can introduce moderate Zr4+ doping and obtain high-quality coating layers. This work offers a guidance for industrial to enhance electrochemical performances of Ni-rich NCM cathode materials during surface modification processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single-crystal NCM111 (SC-NCM) is obtained from a ternary MOF precursor. • SC-NCM can be operated at a high cut-off voltage with good cyclability. • Specific capacity can be boosted at a large operation range of 2.8–4.6 V. • Enhanced performance can be attributed to better microstructural stability. Single-crystal NCMs show properties of good cyclability and high safety, and considers as promising cathode materials for next generation lithium batteries. But industrial production of single-crystal NCMs should overcome problems of lengthy production steps, high production costs and poor consistency. In this work, a Ni-Co-Mn ternary MOF has been developed for NCM cathode materials preparation. The MOF derived precursors show high activity and can be used to prepare single-crystal NCM111 (SC-NCM) in a regular sintering process. As-prepared SC-NCM cathode materials show an average particle size of 400 nm, reveal a polyhedral structure with smooth surface, and can be applied as a high-voltage cathode with excellent cyclability and high specific capacities. Specifically, it is delivery a high discharge capacity of 172 mAh g−1 and maintains 156 mAh g−1 after 50 cycles in a large potential range of 2.8–4.6 V at a high current of 1 C; it also reveals a good capacity retention of 88.3 % after 600 cycles. The enhanced electrochemical performance can be attributed to the SC-NCM reveals a good microstructural stability, which prevents the unexpected structural degradation and microcrack generation during battery cycling. This work provides a new method to synthesis the high-quality single-crystal NCM materials with good electrochemical performance. [ABSTRACT FROM AUTHOR]

Calcium phosphate (CaP) materials are optimal candidate biomaterials for bone tissue engineering because of their bioactivity and biocompatibility. The controlled fabrication of CaP materials draws great interest because the size, shape and composition of CaP crystals play critical roles in biological response. In this study, CaP nanowires and microspheres were synthesised via an organic-free hydrothermal process without the assistance of any surfactant or template. The effect of the reaction condition on CaP crystal growth was investigated. Experimental results showed that the size, shape and composition of the obtained CaP crystals could be manipulated by changing nucleation temperature, reaction temperature, pH value and reaction time. The chemical composition of the obtained crystals had a common change process from dicalcium phosphate dihydrate and dicalcium phosphate anhydrous to hydroxyapatite with the elongation of reaction time. The prenucleation and nucleation temperature before hydrothermal treatment were critical for the growth of CaP crystal. Two typical morphologies of nanowire and microsphere were fabricated under the given reaction condition. The growth mechanisms of the crystals were also discussed in this paper. In vitro results showed that both nanowires and microspheres of CaP exhibited exceptional performance to improve osteoblast proliferation, which endowed them with interesting potential for bone repair. The findings are highly important to develop excellent materials suitable for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Electroless plating occupies a vital position in the fields of metal anticorrosion while accompanied by a large amount of effluent containing organophosphorus (like phytic acid) and heavy metals ions {like Cu (II) and Ni (II)}. However, it was still remaining great challenges in how to simultaneously remove these organophosphorus and heavy metal ions with simple methods. This work prepared a green, clean and efficient adsorbent amino-functionalized cellulose (AFCA) for simultaneous removal of organophosphorus and metal ions from complex wastewater. Benefitting from its abundant amino groups, AFCA can rapidly remove organophosphorus and metal ions within 10 min. The theoretical maximum adsorption capacities of AFCA could also reach as high as 89.29 mg/g, 79.37 mg/g and 178.57 mg/g, respectively. Most importantly, for the mixed system of organophosphorus and Cu (II), the removal efficiency was increased by 5.66% and 30.23% compared with the individual system, respectively. High simultaneous removal capacity of AFCA was due to the hydrogen bond and electrostatic interactions with organophosphorus and the complexation interactions between abundant amino groups and metal ions. All of these results demonstrate that AFCA has enormous potential for the treatment of actual electroless plating effluents. [Display omitted] • Green, clean and efficient adsorbent AFCA was prepared from waste cellulose. • AFCA has abundant active amino groups with a content of 2.6 mmol/g. • AFCA displayed efficient adsorption of organophosphorus, Cu (II) and Ni (II). • AFCA can simultaneous and synergistic removal of OP and Cu (II) from mixed system. [ABSTRACT FROM AUTHOR]

Abstract: Hydroxyapatite-modified titanate nanowire scaffolds as alternative materials for tissue engineering have been developed via a titanate nanowire matrix assisted electrochemical deposition method. The macroporous titanate nanowire matrix on Ti metal was fabricated by a hydrothermal method, and then followed by an electrochemical synthesis of hydroxyapatite nanoparticles on titanate nanowire. The incorporation of titanate nanowire matrix with high oriented hydroxyapatite nanoparticles generates hierarchical scaffolds with highly osteogenic, structural integrity and excellent mechanical performance. As-prepared porous three dimensional interconnected hydroxyapatite-modified titanate nanowire scaffolds, mimicking the nature’s extracellular matrix, could provide a suitable microenvironment for tissue cell ingrowth and differentiation. The ceramic titanate nanowire core with HA nanoparticle sheath structure displays superhydrophilicity, which facilitates the cell attachment and proliferation, and induces the in vitro tissue-engineered bone. Human osteoblast-like MG63 cells were cultured on the hydroxyapatite-modified titanate nanowire scaffolds, and the results showed that the scaffolds highly promote the bioactivity, osteoconductivity and osteoblast differentiation. [Copyright &y& Elsevier]

• Sericin acts as a biosorbent to anchor iron ions (Fe3+) by coordination. • Fe 3 C is uniformly dispersed in sericin-derived carbon (SC) by in-situ synthesis. • The modification of Fe 3 C to SEI film is confirmed by ex-situ EIS analysis. • Fe 3 C/SC presents high reversible capacity, rate capability and stable cyclability. • The strategy can be used to design other carbon-based materials for energy storage. [Display omitted] Biomass-derived carbon is considered a promising alternative to commercial graphite anode because of its renewability and tunable physical/chemical properties. However, the specific capacity and rate capability of biochar anode materials must be further enhanced to satisfy the increasing energy demand. Here, we report a facile strategy to synthesize uniform Fe 3 C inserted sericin-derived porous carbon (Fe 3 C/SC) via coordination with Fe3+ ions to the carboxylate radicals of sericin protein. The obtained composite retains a hierarchical pore structure with an interconnected carbon scaffold. In particular, the embedded Fe 3 C nanoparticles (NPs) in the carbon matrix will serve as a catalyst for the modification of the solid electrolyte interphase (SEI) layer during the cycles, which effectively enhance reversible capacity. The resulting anode provides high reversible capacity (584.0 mAh g−1 at 0.1 A g−1 after 150 cycles), superior rate capability (259.0 mAh g−1 at 2 A g−1) and remarkable cycling stability under high current density (219.7 mAh g−1 retention at 2 A g−1 after 600 cycles). This composite is expected to be one of the most potential anode materials for lithium-ion batteries, owning to its cost-effective, facile synthesis and efficient performance with excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

There are a variety of silkworms and silk fibroins produced by them. Silks have many inherent suitable properties for biomaterials. In this paper, a novel silk-like hybrid protein, [DGG(A)12GGAASTGRGDSPAAS]5, which consists of polyalanine region of silk fibroin from a wild silkworm, Samia cynthia ricini, and cell adhesive region including Arg-Gly-Asp (RGD) sequence, derived from fibronectin, was designed and produced. The genes encoding the hybrid protein were constructed and expressed in Escherichia coli. The main conformation of the polyalanine region, that is, either α-helix or β-sheet, could be easily controlled by treatment with different acidic solvents, trifluoroacetic acid or formic acid, respectively. This structural change was monitored with 13C CP/MAS NMR. Higher cell adhesive and growth activities of the hybrid protein compared with those of collagen were obtained. [Copyright &y& Elsevier]

The introduction of metal particles (MP) in the phase change materials (PCM) realizes the highly efficient thermal energy storage. However, a suitable carrier is necessary for PCM/MP composites for various applications. In this work, the polyethylene glycol (PEG) was used as PCM, five MPs including copper (Cu), aluminum (Al), silver (Ag), iron (Fe), and zinc (Zn) particles were used, and the viscose fabric was selected as a carrier for coating of PEG/MPs. The PEG was blended with different MPs with the same weight ratio of 72.3:23.7. Then, the PEG/MP-coated viscose fabric was prepared by applying PEG/MP composites on the viscose fabric with the same weight ratio of 90:10 and the PEG-coated viscose fabric (86.7:13.3) was set as reference. The phase transition of the prepared PEG/MP composites and the PEG/MP-coated viscose fabrics was investigated via the differential scanning calorimetry (DSC). The thermal behavior of the PEG/MP-coated viscose fabric was investigated via Alambeta device and the T-history method. The results revealed that the enthalpy of all the PEG/MP-coated viscose fabrics were larger than 100J/g. Besides, only the higher theoretical enthalpy of the PEG in the PEG/MP composites was found, and the MPs assisted in the higher crystallization of PEG. Results from the Alambeta device proved that the thermal conductivity was increased when MPs were introduced in the coated viscose fabric. T-history curves of all the PEG/MP-coated viscose fabric revealed that the heating constant of the phase transition stage mainly accounted for the quick heat transfer. • Metal particles (MPs) were considered as the good nuclei sites for the PEG nucleation while the viscose fiber did not. • Newton's cooling law was proposed to evaluate the T-history of PEG/MP-coated viscose fabric. • Higher efficient thermal energy storage relied on the improved heating constant of the phase transition stage. [ABSTRACT FROM AUTHOR]

In recent years, shape memory polyurethane (SMPU) as a smart material has been used in various applications owing to its desirable shape memory effect and biocompatibility. In this study, unidirectional SMPU nanofibers are innovated by electrospinning to clarify the mechanical and shape memory properties with nanofiber directions. The results showed that when the nanofiber alignment degree is 0° (parallel to the tensile direction), the aligned SMPU nanofibers achieved the obvious improvement of tensile strength (increased to 135%) and elastic modulus (increased to 313%), compared with the random SMPU nanofiber. Moreover, the developed aligned nanofibers exhibited good ability against stress relaxation and creep under constant strain or constant stress conditions in cyclic loading. The aligned SMPU nanofibers with a 0° alignment degree exhibited excellent shape memory properties with shape recovery rates larger than 93% and shape fixity rates larger than 90%, and a dramatic increase of shape recovery stress. • The aligned shape memory polyurethane (SMPU) nanofibers are developed with different alignment degrees. • High performance of shape memory and recovery property is obtained by the aligned SMPU nanofibers. • The relationships between shape fixity, shape recovery ratio and nanofiber alignment are investigated systemically. • Obvious improvement of mechanical properties with 0° nanofibers is identified. • The mechanism of shape memory effect with aligned nanofibers are clarified. [ABSTRACT FROM AUTHOR]

The popularity of flexible energy harvesters has grown rapidly in recent decades because of their high flexibility for application in wearable and implantable devices. Flexibility and functionality are key issues for their use in wider engineering applications. In this study, we present a multifunctional flexible energy harvester based on aligned lead zirconate titanate (PZT)/shape memory polyurethane (SMPU) nanofibers and applying its shape memory properties for use with surfaces with curved and/or complex structures. Mechanical and thermomechanical analyses and energy harvesting tests were performed on random and aligned nanofibers to investigate the influence of nanofiber orientation and its shape memory properties. Our results showed that, compared with random nanofibers, 0° aligned PZT/SMPU nanofibers (the nanofibers' direction is parallel to the tensile direction) demonstrated higher mechanical, shape memory and energy harvesting properties. In particular, the energy harvesting properties (output voltages) were increased by 5.4 times. In addition, taking advantage of the shape memory effect, the PZT/SMPU energy harvester can be deformed into various curved shapes to match complex structures while maintaining its original piezoelectric characteristics, which resulted in enhanced energy harvesting from curved surfaces. The developed energy harvester realized better piezoelectricity as a result of its nanofiber arrangement, and offers a flexible ability to match various surfaces with complex structures to achieve more effective energy harvesting. [ABSTRACT FROM AUTHOR]