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The hydrophobicity and inertness of the polypropylene (PP) material surface usually lead to serious biofouling and bacterial infections, which hamper its potential application as a biomedical polymer. Many strategies have been developed to improve its antifouling or antibacterial properties, yet designing a surface to achieve both antifouling and antibacterial performances simultaneously remains a challenge. Herein, we construct a dual-function micropatterned PP surface with antifouling and antibacterial properties through plasma activation, photomask technology and ultraviolet light-induced graft polymerization. Based on the antifouling agent poly(2-methacryloyloxyethyl phosphate choline) (PMPC) and the antibacterial agent quaternized poly(N,N-dimethylamino)ethyl methacrylate (QPDMAEMA), two different micropatterning structures have been successfully prepared: PP-PMPC-QPDMAEMA in which QPDMAEMA is the micropattern and PMPC is the coating polymer, and PP-QPDMAEMA-PMPC in which PMPC is the micropattern and QPDMAEMA is the coating polymer. The composition, elemental distribution and surface morphology of PP-PMPC-QPDMAEMA and PP-QPDMAEMA-PMPC have been thoroughly characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), respectively. Compared with pristine PP, the two types of micropatterned PP films exhibit good surface hydrophilicity as characterized by water contact angle measurements. The results of anti-protein adsorption, platelet adhesion and antibacterial evaluation showed that PP-PMPC-QPDMAEMA and PP-QPDMAEMA-PMPC had good anti-protein adsorption properties, especially for lysozyme (Lyz). They can effectively prevent platelet adhesion, and the anti-platelet adhesion performance of PP-QPDMAEMA-PMPC is slightly better than that of the PP-PMPC-QPDMAEMA sample. The sterilization rate of S. aureus and E. coli is as high as 95% for the two types of micropatterned PP films. Due to the rational design of micropatterns on the PP surface, the two classes of dual-functional PP materials realize both the resistance of protein and platelet adhesion, and the killing of bacteria at the same time. We anticipate that this work could provide a design strategy for the construction of multifunctional biomedical polymer materials. [ABSTRACT FROM AUTHOR]

Heavy metal ions have attracted considerable concern for their high toxicity and potential malign effects on the water environment, and adsorption has been regarded as one of the most versatile and effective techniques towards water treatment. In view of this, hierarchical porous carnation-like Ca4B10O19·7H2O microspheres self-assembled by two-dimensional (2D) quasi-hexagonal nanoplates are successfully synthesized for the first time as far as we know, by a facile and surfactant ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) assisted hydrothermal approach using CaCl2·2H2O, NaOH and H3BO3 as the raw materials. The as-obtained carnation-like Ca4B10O19·7H2O microspheres exhibit a uniform morphology, ca. 89% of which have a diameter within the range of 8.0–11.0 μm. A probable EDTA-2Na assisted self-assembly formation mechanism has also been proposed based on systematic control experiments. Meanwhile, the carnation-like Ca4B10O19·7H2O microspheres demonstrate a transparent characteristic from the ultraviolet to the visible region, a hierarchical porous structure (specific surface area: 32.79 m2 g−1, pore volume: 0.151 cm3 g−1, average pore diameter: 3.704 nm) and satisfactory thermal stability. In addition, the carnation-like microspheres are confirmed as great satisfactory adsorbents for heavy metal ion (Pb2+) removal with an adsorption capacity qm of 256.4 mg g−1, which may also be employed as excellent adsorbent candidates for other heavy metal or organic dye removal in water treatment as well as catalyst carriers in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Polymer materials with high biocompatibility and versatile functions are urgently required in the biomedical field. The hydrophobic surface and inert traits of polymer materials usually encounter severe biofouling and bacterial infection which hinder the potential application of polymers as biomedical materials. Although many antifouling or antimicrobial coatings have been developed for modification of biomedical devices/implants, few can simultaneously fulfill the requirements for antimicrobial and antifouling activities. Herein, we constructed bifunctional micropatterns with antifouling and antimicrobial properties onto polypropylene (PP) films using argon plasma activation treatment, photomask technique and UV-initiated graft polymerization method. Different sizes of PMPC/PTM/PEGDA micropatterns were fabricated on PP films to yield patterned PP–PMPC/PTM/PEGDA as evidenced by infrared (IR) spectroscopy, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), where PMPC is poly(2-methacryloyloxyethyl phosphorylcholine) for enhancement of hydrophilicity and biocompatibility, PTM is poly(methacryloyloxyethyltrimethylammonium chloride) for contribution to antimicrobial activity and PEGDA is poly(ethylene glycol diacrylate) as the crosslinker. The surface hydrophilicity of patterned PP–PMPC/PTM/PEGDA was characterized by the static water contact angle test. The results showed that the PP sample with a micropattern with the size of 5 μm exhibited the best hydrophilicity. For biological assays of patterned PP–PMPC/PTM/PEGDA, the micropattern size at 5 μm performed the best for both antiplatelet adhesion and antimicrobial activities. We anticipate that this work could provide a new method for building bifunctional biomedical materials to promote the application of PP in biomedical fields. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) nanostructured metal borates have drawn considerable attention owing to their versatile applications in a multitude of fields, but it is still a great challenge to achieve a high aspect ratio in these materials via a facile and feasible route. Herein, ultralong Ca2B2O5·H2O nanowires with a length of 110–230 μm and ultrahigh aspect ratio of 240–750 are successfully synthesized for the first time via a facile water-bath pretreated eco-friendly hydrothermal technique in the absence of any additives, using low cost CaCl2, H3BO3 and NaOH as the raw materials. The formation mechanism of the ultralong nanowires is studied in detail by varying the process parameters (water-bath and hydrothermal temperature, duration time, etc.). The water-bath treatment plays a key role in the formation of thin hexagonal Ca(OH)2 nanoplates, favoring subsequent conversion to ultralong nanowires with a high aspect ratio. The as-obtained Ca2B2O5·H2O:5.0%RE3+ (rare earth, RE = Eu, Tb) nanophosphors exhibit strong photoluminescence emission and excitation performance, with corresponding Commission Internationale de l'Eclairage (CIE) values determined as (0.635, 0.364) and (0.320, 0.597) within the red and green regions, respectively. This not only suggests that the ultralong Ca2B2O5·H2O nanowires are promising structure- and function-integrated photoluminescent host candidates, but also provides a novel and facile route for the formation of high aspect ratio 1D nanostructures of other metal borates. [ABSTRACT FROM AUTHOR]

Three-dimensional hierarchical nanoarchitectures of metal borates self-assembled by one-dimensional or two-dimensional nanostructures have been paid extensive attention for their versatile compositions and excellent performance in various fields. Hilgardite-like metal borates have been widely employed as nonlinear optical materials and ideal hosts for various luminescent ions. In this contribution, we reported for the first time a mild surfactant-assisted hydrothermal process for the synthesis of uniform Ba2(B5O9)Cl·(H2O)0.5 microspheres at 160 °C for 6.0 h, by using BaCl2·2H2O, H3BO3, and NaOH as raw materials and ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) as the surfactant. The effects of process parameters and the EDTA-2Na assisted formation mechanism were investigated in detail. The as-obtained microspheres exhibited a transparent characteristic from the ultraviolet to visible range. Within the experimental doping molar percentage of 0–10% in Ba2+, the as-prepared Ba2(B5O9)Cl·(H2O)0.5:6%Tb3+ phosphors demonstrated the strongest PL intensity, revealing the as-obtained Ba2(B5O9)Cl·(H2O)0.5 microspheres as a great promising host candidate for emitting luminescent materials in light display systems or optoelectronic devices. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) hierarchical porous structures self-organized by one-dimensional (1D) building blocks have attracted considerable attention due to their unique properties and versatile applications. Herein, uniform hierarchical porous MgBO2(OH) superstructures with a microsphere-like profile were synthesized for the first time via a facile ionothermal synthesis (150 °C, 12.0 h) using MgCl2, H3BO3 and NaOH as the raw materials, and N,N-dimethylformamide nitrate ionic liquid as the solvent. The porous MgBO2(OH) microspheres exhibited a specific surface area of 57.22 m2 g−1, 82.4% of which had a diameter within the range of 4.0–6.0 μm. The subsequent mild thermal conversion (600 °C, 12.0 h) gave rise to the hierarchical porous Mg2B2O5 microspheres with high crystallinity and a specific surface area of 24.20 m2 g−1. The synergistic effect of the hydrophilic surfaces of the MgBO2(OH) nanostructures and the ionothermally confined self-organization co-contributed to the formation of the hierarchical porous MgBO2(OH) and Mg2B2O5 superstructures, which were employed as adsorbents for Congo red (CR) in simulated waste water. Both MgBO2(OH) and Mg2B2O5 superstructures exhibited good recyclability and reusability as high efficient adsorbents for dye removal after regeneration. The Langmuir isothermal model well interpreted the adsorption behavior of CR. The intra-particle diffusion model was also well fitted based on the kinetic data, indicating microsphere diffusion as the rate-limiting step. The maximum adsorption capacities, qm, for CR onto the porous MgBO2(OH) and Mg2B2O5 superstructures, which were calculated from the Langmuir isothermal model, were 228.3 and 139.3 mg g−1, respectively. The present ionothermally confined self-organization for the hierarchical porous MgBO2(OH) and Mg2B2O5 superstructures provide new insights into the material chemistry, as well as a controllable ionothermal route for hierarchical borate nanoarchitectures. In addition, these superstructures provide a new platform for dye adsorption, and other potential fields, such as heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

This communication describes the design and synthesis of anti-sintering and -coke nickel phyllosilicate (PS) nanotubes (Ni/PSn) for hydrogen production via reforming reactions. The introduction of nickel particles in PS nanotubes could effectively maintain the Ni size and increase the resistance of metal particles for carbon deposition. [ABSTRACT FROM AUTHOR]