Robust Aqua Material: A Pressure‐Resistant Self‐Assembled Membrane for Water Purification

“Aqua materials” that contain water as their major component and are as robust as conventional plastics are highly desirable. Yet, the ability of such systems to withstand harsh conditions, for example, high pressures typical of industrial applications has not been demonstrated. We show that a hydrogel‐like membrane self‐assembled from an aromatic amphiphile and colloidal Nafion is capable of purifying water from organic molecules, including pharmaceuticals, and heavy metals in a very wide range of concentrations. Remarkably, the membrane can sustain high pressures, retaining its function. The robustness and functionality of the water‐based self‐assembled array advances the idea that aqua materials can be very strong and suitable for demanding industrial applications.     

Synthesis and electrochemical performances of amorphous carbon-coated Sn–Sb particles as anode material for lithium-ion batteries

The amorphous carbon coating on the Sn–Sb particles was prepared from aqueous glucose solutions using a hydrothermal method. Because the outer layer carbon of composite materials is loose cotton-like and porous-like, it can accommodate the expansion and contraction of active materials to maintain the stability of the structure, and hinder effectively the aggregation of nano-sized alloy particles. The as-prepared composite materials show much improved electrochemical performances as anode materials for lithium-ion batteries compared with Sn–Sb alloy and carbon alone. This amorphous carbon-coated Sn–Sb particle is extremely promising anode materials for lithium secondary batteries and has a high potentiality in the future use.     

Synthesis of poly{[bis(diethynylphenyl)silylene]phenylene}s with highly heat-resistant properties and an application to conducting materials

Poly{[bis(3,5-diethynylphenyl)silylene]-p-phenylene} was prepared by the reaction of poly[(diethoxysilylene)-p-phenylene] with 3,5-bis(trimethylsilylethynyl)phenyllithium, followed by desilylation of the resulting substitution product. The present polymer exhibited extremely high heat-resistance and their thermogravimetric analysis (TGA) in a nitrogen atmosphere showed the temperature of 5% weight loss (Td₅) of 791 °C. Total weight loss at 1000 °C in TGA was determined to be 6% based on the initial weight. Treatment of a polymer film on a quartz plate at 1200 °C in vacuo led to the formation of a conducting thin film with a thickness of 74 nm and a conductivity of 9 S/cm.     

A 3D Organically Synthesized Porous Carbon Material for Lithium‐Ion Batteries

We report the first organically synthesized sp–sp³ hybridized porous carbon, OSPC‐1. This new carbon shows electron conductivity, high porosity, the highest uptake of lithium ions of any carbon material to‐date, and the ability to inhibit dangerous lithium dendrite formation. The new carbon exhibits exceptional potential as anode material for lithium‐ion batteries (LIBs) with high capacity, excellent rate capability, long cycle life, and potential for improved safety performance.     

A Sustainable Freeze‐Drying Route to Porous Polysaccharides with Tailored Hierarchical Meso‐ and Macroporosity

Bio‐derived polysaccharide aerogels are of interest for a broad range of applications. To date, these aerogels have been obtained through the time‐ and solvent‐intensive procedure of hydrogel fomation, solvent exchange, and scCO2 drying, which offers little control over meso/macropore distribution. A simpler and more versatile route is developed, using freeze drying to produce highly mesoporous polysaccharide aerogels with various degrees of macroporosity. The hierarchical pore distribution is controlled by addition of different quantities of t‐butanol (TBA) to hydrogels before drying. Through a systematic study an interesting relationship between the mesoporosity and t‐butanol/water phase diagram is found, linking mesoporosity maxima with eutectic points for all polysaccharides studied (pectin, starch, and alginic acid). Moreover, direct gelation of polysaccharides in aqueous TBA offers additional time savings and the potential for solvent reuse. This finding is a doorway to more accessible polysaccharide aerogels for research and industrial scale production, due to the widespread accessibility of the freeze drying technology and the simplicity of the method.

     

Pumping through Porous Hydrophobic/Oleophilic Materials: An Alternative Technology for Oil Spill Remediation

Recently, porous hydrophobic/oleophilic materials (PHOMs) have been shown to be the most promising candidates for cleaning up oil spills; however, due to their limited absorption capacity, a large quantity of PHOMs would be consumed in oil spill remediation, causing serious economic problems. In addition, the complicated and time‐consuming process of oil recovery from these sorbents is also an obstacle to their practical application. To solve the above problems, we apply external pumping on PHOMs to realize the continuous collection of oil spills in situ from the water surface with high speed and efficiency. Based on this novel design, oil/water separation and oil collection can be simultaneously achieved in the remediation of oil spills, and the oil sorption capacity is no longer limited to the volume and weight of the sorption material. This novel external pumping technique may bring PHOMs a step closer to practical application in oil spill remediation.     

甲壳素基新材料研究进展

甲壳素/壳聚糖良好的生物相容性、生物可降解性及独特的生理活性使其成为非常有应用价值的天然高分子材料,当前已成为新材料领域的研究热点.甲壳素/壳聚糖具有良好的可加工性能,可固定贵金属、半导体纳米材料等活性催化物质,同时其本身也具有催化作用,是一类绿色环境友好的高分子催化材料.良好的生物相容性和生物可降解性使甲壳素/壳聚糖...     

Se-directed synthesis of polymeric carbon nitride with potential applications in heavy metal-containing industrial sewage treatment

By calcining melamine at 500 °C with selenium powder as the structure director, polymeric carbon nitride could be prepared with enhanced specific surface area and mesoporous volume. Compared with the material fabricated without Se, this cost-effective Se-incorporated PCN (PCN-Se) could adsorb heavy metals (such as Ni, Cu and Pb) much more efficiently. Materials characterizations such as SEM, TEM and XPS demonstrated that the enlarged specific surface area and total mesoporous volume as well as the interaction of the incorporated Se with the metals via coordination should be the promoting factors for the advanced performances of the novel materials.     

高折射率聚合物-无机纳米光学杂化材料的设计与制备及其应用

传统的高折射率聚合物光学材料,可以通过向聚合物中引入一些芳香环,含硫基团以及除氟以外的其他卤素原子来提高聚合物光学材料的折射率,但是就目前的研究现状来看,这类纯聚合物光学材料的折射率一般都低于1.8.而将具有高折射率的无机纳米粒子引入到聚合物中,所制备的聚合物-无机纳米光学材料的折射率能够达到1.8以上.而且这类高折射率聚合物-无机纳米光学杂化材料同时具有高分子光学材料和无机材料的双重优点,具有广泛的应用前景.鉴于当前高折射率聚合物-无机纳米光学杂化材料发展之迅速和其研究与开发的重要性,并结合目前国内外的研究现状,本文就高折射率聚合物-无机纳米光学杂化材料的设计、制备方法及其相关应用做一个比较系统的介绍,同时对这类材料在未来研究中所应注意的问题也提出了相应的看法.     

Modulating Hierarchical Micro/Mesoporosity by a Mixed Solvent Approach in Al-MOF: Stabilization of MAPbBr3 Quantum Dots

Various hierarchical micro/mesoporous MOFs based on {[Al(μ-OH)(1,4-NDC)]⋅H₂O} ( MOF1 ) with tunable porosities (pore volume and surface area) have been synthesized by assembling Al^III and 1,4-NDC (1,4-naphthalenedicarboxylate) under microwave irradiation by varying water/ethanol solvent ratio. Water/ethanol mixture has played a crucial role in the mesopore generation in MOF1M₂₅ , MOF1M₅₀ , and MOF1M₇₅ , which is achieved by in situ formation of water/ethanol clusters. By adjusting the ratio of water/ethanol, the particle size, surface area and micro/mesopore volume fraction of the MOFs are controlled. Furthermore, reaction time plays a critical role in mesopore formation as realized by varying reaction time for the MOF with 50 % ethanol ( MOF1M₅₀ ). Additionally, hierarchical MOF ( MOF1M₅₀ ) has been used as a template for the stabilization of MAPbBr₃ (MA=methylammonium) perovskite quantum dots (PQDs). MAPbBr₃ PQDs are grown inside MOF1M₅₀ , where mesopores control the size of PQDs which leads to quantum confinement.     

A Novel Quasi-Planar Two-dimensional Carbon Sulfide with Negative Poisson's Ratio and Dirac Fermions

In the present study, a novel and unconventional two-dimensional (2D) material with Dirac electronic features has been designed using sulflower with the help of density functional theory methods and first principles calculations. This 2D material comprises of hetero atoms (C, S) and belongs to the tetragonal lattice with P₄/nmm space group. Scrutiny of the results show that the 2D nanosheet exhibits a nanoporous wave-like geometrical structure. Quantum molecular dynamics simulations and phonon mode analysis emphasize the dynamical and thermal stability. The novel 2D nanosheet is an auxetic material with an anisotropy in the in-plane mechanical properties. Both composition and geometrical features are completely different from the conditions necessary for the formation of Dirac cones in graphene. However, the presence of semi-metallic nature, linear band dispersion relation, massive fermions and massless Dirac fermions are observed in the novel 2D nanosheet. The massless Dirac fermions exhibit highly isotropic Fermi velocities (v_f=0.68×10⁶ m/s) along all crystallographic directions. The zero-band gap semi metallic features of the novel 2D nanosheet are perturbative to the electric field and external strain.     

Biotemplated Hierarchical Porous Material: The Positively Charged Leaf

Addressing the problem of pathogenic bacteria in human health remains a great challenge. We have prepared MgO, replicated from the leaf template, for efficient bacterial removal. The synthesis method perfectly inherits the advantage of the hierarchical three‐level micro‐meso‐macroporous structure from the leaf template. The final product has the integrated advantages of a positively charged property, hierarchical three‐level micro‐meso‐macroporous microstructure and sterilization property so that it could be named “the positively charged leaf”. The positively charged leaf with the microstructure, which is bestowed by Nature, could be utilized in water purification for dye removal and could be extended to pollutant removal, especially of harmful bacteria. The positively charged leaf, as the leaf shield, could be useful in protecting human health. The concept of this work could be applied to the synthesis of different functional metal oxides with hierarchical porous structures, and the products could be utilized in efficient bacterial removal.     

High-capacity porous carbons prepared by KOH activation of activated carbon for supercapacitors

High-performance supercapacitor electrode materials are prepared from the commercially available activated carbon （AC） through a facile and low-cost chemical activation method. The obtained results show that AC activated by KOH with an alkali/carbon ratio of 6/1 （ACK6） possesses a specific surface area of 3405 m^2/g, a large pore volume of 2.01 cm^3/g, and exhibits the highest initial specific capacitance of 335 F/g at the current density of 0.5 A/g in 6 mol/L KOH, and 85% coloumbic efficiency for 5000 cycles at 20 mV/s.     

有机荧光防伪材料的制备

１引言随着社会的不断进步,工农业的发展,档次各异、琳琅满目的商品在促进商品经济高速发展的同时,也满足了人们不断提高的物质生活水平的需要。然而,令人讨厌的伪品也龙蛇混杂地进入了流通市场。伪币、伪票、伪商标掩护下的伪品以及伪证书等常使人受骗,蒙受损失。因...     

Ionic liquids for soft functional materials with carbon nanotubes

A serendipitous finding that ionic liquids gel with carbon nanotubes has opened a new possibility of ionic liquids as modifiers for carbon nanotubes. Upon being ground into ionic liquids, carbon nanotube bundles are untangled, and the resultant fine bundles form a network structure. This is due to the possible specific interaction between the imidazolium ion component and the pi-electronic nanotube surface. The resultant gelatinous materials, consisting of highly electroconductive nanowires and fluid electrolytes, can be utilized for a wide variety of electrochemical applications, such as sensors, capacitors, and actuators. Ionic liquids allow for noncovalent and covalent modifications of carbon nanotubes and fabrication of polymer composites with enhanced physical properties. The processing of carbon nanotubes with ionic liquids is not accompanied by the disruption of the pi-conjugated nanotube structure and does not require solvents; therefore it can readily be scaled up. This article focuses on new aspects of ionic liquids for designer soft materials based on carbon nanotubes.