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.     

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.     

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.     

非水系锂氧气电池正极材料研究现状

锂氧气电池因其具有接近汽油的比能量密度而备受人们的关注。随着研究的深入,研究人员发现锂氧气电池的实用化面临着诸多挑战,如高的过电位、循环性能不佳、能量效率难以保持较高水平等。这一系列问题直接与负极的腐蚀、电解液的分解、正极材料的结构和ORR/OER催化剂催化活性有着非常紧密的联系。本文着重对近三年非水系锂氧气电池正极材料的研究进行综述,将锂氧气电池正极材料的研究分为碳基复合材料和无碳基复合材料进行概括,阐述了不同类别的催化剂和正极材料微观结构对锂氧气电池的充放电性能、循环稳定性、循环效率等性能的影响,并对后续的研究工作做一定的展望。     

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.     

分子印迹材料研究进展

本文简要综述了分子印迹的原理、制备技术,着重介绍了与膜材料、磁性材料、纳米材料和复合材料相结合的分子印迹技术的应用与发展。     

无机非线性光学材料的研究进展

从实验合成的角度总结了无机非线性光学材料的发展现状 ,分析了这个研究领域的发展趋势。     

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.     

贮氢材料及其应用研究进展

贮氢材料是一类新型高性能材料。本文对现有贮氢材料进行了合理的分类,对贮氢材料及其应用研究进展进行了综述。     

Study of adsorption properties of synthesized mesoporous silica doped with dysprosium and modified with nickel

Mesoporous silica (MPS) modified with nickel and MPS doped with dysprosium and modified with nickel have been synthesized by the template method. The adsorbents are characterized by various techniques such as transmission electron microscopy, scanning electron microscopy, X-ray diffraction, inductively coupled plasma spectroscopy, and X-ray fluorescence analyses. The adsorption properties of the synthesized samples have been investigated by inverse gas chromatography. Furthermore, thermodynamic characteristics of the adsorption of test compound belonging to different classes of organic compounds were obtained. In addition, the contributions of the energy of specific interactions to the total adsorption energy were calculated. It is also shown that entropy plays the determining role in the adsorption of test compounds on synthesized mesoporous materials.     

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.     

冷冻干燥法制备聚合物基新型材料及其应用

冷冻干燥法是一种环境友好、经济高效的制备通孔先进材料的成型方法,采用冷冻干燥技术高效可控地构筑多孔结构材料备受关注.近年来采用冷冻干燥法制备出的聚合物基新型材料,在不同功能材料领域展现出广阔的应用前景.本文综述了国内外通过冷冻干燥法制备聚合物新型材料的研究进展,对其在生物医学、环境保护、导电以及气体检测方面的应用进行了总结,并展望了其发展趋势.     

Luminescent Thermochromism of 2D Coordination Polymers Based on Copper(I) Halides with 4‐Hydroxythiophenol

Solvothermal reactions between copper(I) halides and 4‐mercaptophenol give rise to the formation of three coordination polymers with general formula [Cu₃X(HT)₂]_n (X=Cl, 1 ; Br, 2 ; and I, 3 ). The structures of these coordination polymers have been determined by X‐ray diffraction at both room‐ and low temperature (110 K), showing a general shortening in Cu?S, Cu?X and Cu?Cu bond lengths at low temperatures. 1 and 2 are isostructural, consisting of layers in which the halogen ligands act as μ₃‐bridges joining two Cu1 and one Cu2 atoms whereas in 3 the iodine ligands is as μ₄‐mode but the layers are quasi‐isostructural with 1 or 2 . These compounds show a reversible thermochromic luminescence, with strong orange emission for 1 and 2 , but weaker for 3 at room temperature, whereas upon cooling at 77 K 1 and 2 show stronger yellow emission, and 3 displays stronger green emission. DFT calculations have been used to rationalize these observations. These results suggest a high potential for this novel and promising stimuli‐responsive materials.     

Graphene: Safe or Toxic? The Two Faces of the Medal

Graphene is considered the future revolutionary material. For its development, it is of fundamental importance to evaluate the safety profile and the impact on health. Graphene is part of a bigger family which has been identified as the graphene family nanomaterials (GFNs). Clarifying the existence of multiple graphene forms allows better understanding the differences between the components and eventually correlating their biological effects to the physicochemical characteristics of each structure. Some in vitro and in vivo studies clearly showed no particular risks, while others have indicated that GFNs might become health hazards. This Minireview critically discusses the recent studies on the toxicity of GFNs to provide some perspective on the possible risks to their future development in materials and biomedical sciences.     

Development of Sulfonic-Acid-Functionalized Mesoporous Materials: Synthesis and Catalytic Applications

Sulfonic acid based mesostructures (SAMs) have been developed in recent years and have important catalytic applications. The primary applications of these materials are in various organic synthesis reactions, such as multicomponent reactions, carbon–carbon bond couplings, protection reactions, and Fries and Beckman rearrangements. This review aims to provide an overview of the recent developments in the field of SAMs with a particular emphasis on the reaction scope and advantages of heterogeneous solid acid catalysts.     

计算单向复合材料弹性模量的新公式

根据复合材料单层的实际构造，提出了串并联组合模型，采用微观力学与宏观力学相结合的方法，推导出一组计算单向复合材料弹性模量的新公式。其优点是：Ｅ１和ｖ（１２）、Ｅ２和Ｇ（１２）的计算式形式对称，结构简单，计算容易，物理意义明确。我们把由世界上许多著名学者提出的多组预测公式和本文导出式计算所得的结果与国内外已发表的硼／环氧、碳／环氧、玻璃／环氧复合材料的实验数据相比较，结果表明：导出式比其他公式精确、更有价值，可供二程设计使用。     

pH‐Sensitive Mechanical Properties of Elastin‐Based Hydrogels

Ionizable amino acids in protein‐based hydrogels can confer pH‐responsive behavior. Because elastin‐like polypeptides (ELPs) have an established sequence and can crosslink to form hydrogels, they are an ideal system for creating pH‐sensitive materials. This study examines different parameters that might affect pH‐sensitive behavior and characterizes the mechanical and physical properties between pH 3 and 11 of three ELP‐based crosslinked hydrogels. The first finding is that varying the amount of crosslinker affects the overall stiffness and resilience of the hydrogels but does not strongly affect water content, swelling ratio, or pH sensitivity. Second, the choice of two popular tag sequences, which vary in histidine and aspartic acid content, does not have a strong effect on pH‐sensitive properties. Last, selectively blocking lysine and tyrosine residues through acetylation significantly decreases the pH‐sensitive zeta potential. Acetylated hydrogels also demonstrate different behavior at low pH values with reduced swelling, reduced water content, and higher stiffness. Overall, this work demonstrates that ELP hydrogels with ionizable groups are promising materials for environmentally‐responsive applications such as drug delivery, tissue engineering, and microfluidics.