Polysaccharide‐Based Oleogels Prepared with an Emulsion‐Templated Approach

The preparation and characterization of oleogels structured by using a combination of a surface‐active and a non‐surface‐active polysaccharide through an emulsion‐templated approach is reported. Specifically, the oleogels were prepared by first formulating a concentrated oil‐in‐water emulsion, stabilized with a combination of cellulose derivatives and xanthan gum, followed by the selective evaporation of the continuous water phase to drive the network formation, resulting in an oleogel with a unique microstructure and interesting rheological properties, including a high gel strength, G′>4000 Pa, shear sensitivity, good thixotropic recovery, and good thermostability.     

Interconnected sandwich structure carbon/Si-SiO2/carbon nanospheres composite as high performance anode material for lithium-ion batteries

In the present work,an interconnected sandwich carbon/Si-SiO2/carbon nanospheres composite was prepared by template method and carbon thermal vapor deposition（TVD）.The carbon conductive layer can not only efficiently improve the electronic conductivity of Si-based anode,but also play a key role in alleviating the negative effect from huge volume expansion over discharge/charge of Si-based anode.The resulting material delivered a reversible capacity of 1094 mAh/g,and exhibited excellent cycling stability.It kept a reversible capacity of 1050 mAh/g over 200 cycles with a capacity retention of 96%.     

Recent advances in polymer network liquid crystal spatial light modulators

Polymer network liquid crystal (PNLC) spatial light modulators are attractive for display and photonic applications because they can achieve submillisecond response time while keeping a large phase change. However, their on-state scattering caused by the grain boundary of LC multidomains hinders their applications. In this article, we review recent progress on the development of scattering-free PNLCs extending from short-wavelength infrared to visible region by reducing the domain sizes to ∼200 nm through low temperature curing process. To reduce operation voltage, both transmissive and reflective modes, LC material properties (birefringence and dielectric anisotropy), polymer composition and concentration, and pretilt angle effect are analyzed. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 183–192     

基于MCM-41硬模板的镍铁磁性纳米管的合成及其磁性研究

以Si-MCM-41为硬模板,利用介孔材料的吸附作用,将Fe3+和Ni 2+按一定比例定量吸附组装到介孔材料的孔壁上;然后通过程序升温在900℃条件下高温焙烧,并经氢氟酸处理,得到直径大约为3.0nm的中空铁氧体纳米管.分别利用傅立叶变换红外光谱仪、扫描电镜、透射电镜、X射线衍射仪分析了合成材料的结构、组成、形貌;采用振动样品磁强计测定了其磁性能.结果表明,合成的镍铁氧体纳米管具有良好的管状形貌,其结构与分子筛MCM-41的结构相似,并具有良好的磁学性能.这说明MCM-41分子筛孔道结构具有可复制性,本研究可望为制备具有适当长径比的一维纳米磁性材料打下良好基础.     

T-symmetric 40-nucleus silver clusters assembled by hetero-anions

We report two anion-templated Ag₄₀ clusters, [Ag₄₀(E)₄(SO₄){S₂P(OEt)₂}₂₄](PF₆)₆ (E = S, 1 ; Se, 2 ). The anionic templates were generated in situ from the decomposition of dithiophosphate (dtp) ligands. The extrusion of sulfur undergoes disproportionation reactions to generate sulfide and sulfate anions, which provide the source of templates in the subsequent cluster assembly reactions. Two Ag₄₀ clusters display high similarity in their structures. The sulfide (selenide) anions and the central sulfate anion reveal a six-coordinate and a rare dodecametallic dodecaconnective pattern, respectively. Four near-equivalent [Ag₁₀(E){S₂P(OEt)₂}₆]²⁺ motifs were assembled via the connection of central sulfate anion to construct Ag₄₀ clusters. The cluster cation, [Ag₄₀(E)₄(SO₄){S₂P(OEt)₂}₂₄]⁶⁺, displayed in T symmetry, is unprecedented in anion-templated silver clusters.     

一步制备高比表面积介孔Co3O4-CeO2及其表征

以有序介孔二氧化硅KIT-6为硬模板,硝酸钴、硝酸铈为金属源,分别在真空辅助条件和普通搅拌条件下制备了介孔CoCeOx复合氧化物。采用XRD、SEM、TEM、N2吸脱附等技术表征了复合氧化物的物化性质,并评价其氧化甲苯的性能。结果表明,在真空辅助和搅拌条件下制备的CoCeOx氧化物是由Co3O4和CeO2组成的介孔Co3O4-CeO2复合氧化物,其比表面积分别为141和89 m^2·g^-1,平均孔径分别为8.7和9.6 nm。真空辅助纳米复制过程有利于金属盐的前驱体充分填充到模板的孔隙中,去除模板后,可以得到有序的介孔复合金属氧化物。所制备介孔钴铈复合氧化物具有孔道有序性好、比表面积大的特点,在挥发性有机化合物的氧化去除方面具有一定的应用前景。     

含骨架铁ZSM-5的合成及其负载Pt催化剂在正十二烷脱氢反应中的催化性能

采用水热合成法使铁进入分子筛MFI骨架结构,成功合成出含骨架铁的分子筛Na-[Fe]-ZSM-5,并通过离子交换法负载Pt制备脱氢催化剂Pt/Na-[Fe]-ZSM-5。通过正十二烷脱氢反应,研究了该催化剂对长链烷烃脱氢制单烯烃反应的催化性能。采用N2吸附-脱附测试、X射线衍射(XRD)、傅立叶变换红外光谱(FT-IR)、氨气程序升温脱附(NH3-TPD)、吡啶吸附的红外光谱(Py-IR)、CO化学吸附、透射电子显微镜(TEM)等不同方法对催化剂进行了表征。结果表明,通过控制骨架铁含量可调控催化剂表面酸性;含骨架铁的ZSM-5分子筛载体具有抑制负载金属晶粒长大,保持金属高分散度的作用;其负载铂催化剂Pt/Na-[Fe]ZSM-5-50具有表面弱酸中心(0.69 mmol·g^-1)和高分散Pt中心,因而具有良好的长链烷烃脱氢活性、稳定性和单烯烃选择;在转化率稳定在~20%时,TOF为4.56 s^-1,单烯烃选择性为92.7%;在实验范围内,Pt/Na-[Fe]ZSM-5催化剂表面弱酸量和脱氢反应的本征活性(TOF)均随催化剂铁含量的增加而增加。     

g-C3N4/Ag/TiO2复合材料的构筑及其光催化性能（英文）

以合成的g-C3N4纳米片和Ag/TiO2空心微球为原料,采用机械搅拌的方法构筑了g-C3N4/Ag/TiO2三元复合光催化剂。采用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、扫描电镜(SEM)、X射线光电子能谱(XPS)、紫外-可见光漫反射(UV-Vis DRS)和光致发光光谱(PL)对g-C3N4/Ag/TiO2进行了表征。研究表明,g-C3N4/Ag/TiO2是由Ag/TiO2微球和g-C3N4纳米片复合而成的。与TiO2相比,其可见光响应范围延长,光生载流子的分离速率加快。在室温下,用降解罗丹明B的反应考察了g-C3N4/Ag/TiO2的可见光催化活性。研究表明,光照180 min时,g-C3N4(0.5%)/Ag/TiO2显示了最高的光催化活性(91.9%),分别是TiO2和Ag/TiO2的7.5和1.8倍。光催化活性的提高与合理的异质结构建和Ag的导电性能有关。     

Highly Sensitive Electrochemiluminescent Insecticide Sensor Based on ZnO Nanocrystals Anchored Nickel Foam for Determination of Imidacloprid in Real Samples

In this work, a novel electrochemiluminescent (ECL) pesticide sensor based on zinc oxide nanocrystals decorated nickel foam is proposed for determination of imidacloprid for the first time. The silica film was used as a morphology‐controlling factor for modification of the electrode with zinc oxide nanocrystals. Zinc oxide was selected as luminescent material due to its cheapness, non‐toxicity, high thermal stability and excellent luminescence properties which truly adhered on the surface of nickel foam. The K₂S₂O₈ was used as strong co‐reactant for this purpose. The silica template plays an important role in controlling the size of ZnO nanocrystals. The Physical morphology of the ZnO/Ni‐foam electrode was performed by electrochemical impedance spectroscopy, Brunauer‐Emmett‐Teller (BET), X‐Ray diffraction analysis, field emission scanning electron microscopy, and energy‐dispersive X‐ray analysis. The ultra‐sensitive electrochemiluminescence method was successfully used for ultra‐trace determination of imidacloprid. The linear dynamic range and low detection limit were obtained 3×10^?14 ?8×10^?8 M and 4.4×10^?15 M, respectively. Also, the relative standard deviation for 15 repetitive optical signals was calculated 1.09 %.The present ECL sensor exhibited superior performance toward the accurate determination of imidacloprid with good reproducibility and stability.     

Templated‐Assembly of CsPbBr3 Perovskite Nanocrystals into 2D Photonic Supercrystals with Amplified Spontaneous Emission

Perovskite nanocrystals (NCs) have revolutionized optoelectronic devices because of their versatile optical properties. However, controlling and extending these functionalities often requires a light‐management strategy involving additional processing steps. Herein, we introduce a simple approach to shape perovskite nanocrystals (NC) into photonic architectures that provide light management by directly shaping the active material. Pre‐patterned polydimethylsiloxane (PDMS) templates are used for the template‐induced self‐assembly of 10 nm CsPbBr₃ perovskite NC colloids into large area (1 cm²) 2D photonic crystals with tunable lattice spacing, ranging from 400 nm up to several microns. The photonic crystal arrangement facilitates efficient light coupling to the nanocrystal layer, thereby increasing the electric field intensity within the perovskite film. As a result, CsPbBr₃ 2D photonic crystals show amplified spontaneous emission (ASE) under lower optical excitation fluences in the near‐IR, in contrast to equivalent flat NC films prepared using the same colloidal ink. This improvement is attributed to the enhanced multi‐photon absorption caused by light trapping in the photonic crystal.