Thixotropic composite hydrogels based on agarose and inorganic hybrid gellants

Water can be used as oxidant in conjunction with metal particles to form metal-water propellant to increase the energy of propellant.For this application,water needs to be stored in form of solid and capable of becoming liquid when use.Stable and thixotropic hydrogel has good potential as water-retaining material and oxidant of metal-based propellant.In this study,we prepared organic/inorganic composite hydrogels by combining inorganic gellants hectorite and fumed silica with organic gellant agarose,respectively.The total content of the gellants can be reduced to less than 2%by adding agarose.The influence of agarose on water content,phase transition temperature,centrifugal stability and other basic physical properties of composite hydrogels were discussed.The results show that the composite hydrogels have better thixotropy and stability than pure inorganic hydrogels,and the gel-sol transformation can be realized by applying shear force or heating to the phase transition temperature.The composite hydrogels have good shear thinning ability and improved mechanical stability.Fumed silica/agarose hydrogels have better physical stability,while the thixotropy and shear thinning ability of hectorite/agarose hydrogels are better.

Ag nanoparticles anchored organic/inorganic Z‐scheme 3DOMM‐TiO_(2‒x)‐based heterojunction for efficient photocatalytic and photoelectrochemical water splitting

Narrow spectral response,low charge separation efficiency and slow water oxidation kinetics of TiO_(2)limit its application in photoelectrochemical and photocatalytic water splitting.Herein,a promising organic/inorganic composite catalyst Ag/PANI/3DOMM‐TiO_(2–x)with a three‐dimensional ordered macro‐and meso‐porous(3DO MM)structure,oxygen vacancy and Ti^(3+)defects,heterojunction formation and noble metal Ag was designed based on the Z‐scheme mechanism and successfully prepared.The Ag/PANI/3DOMM‐TiO_(2–x)ternary catalyst exhibited enhanced hydrogen production activity in both photocatalytic and photoelectrochemical water splitting.The photocatalytic hydrogen production rate is 420.90μmol g^(–1)h^(–1),which are 19.80 times and 2.06 times higher than the commercial P25 and 3DOMM‐TiO_(2),respectively.In the photoelectrochemical tests,the Ag/PANI/3DOMM‐TiO_(2–x)photoelectrode shows enhanced separation and transfer of carriers with a high current density of 1.55 mA cm^(–2)at equilibrium potential of 1.23 V under simulated AM 1.5 G illumination,which is approximately 5 times greater than the 3DOMM‐TiO_(2).The present work has demonstrated the promising potential of organic/inorganic Z‐scheme photocatalyst in driving water splitting for hydrogen production.

Organic-inorganic Hybrids Towards the Preparation of Nanoporous Composite Thin Films for Microelectronic Application

Silicon containing materials have traditionally been used in microelectronic fabrication. Semiconductor devices often have one or more arrays of patterned interconnect levels that serve to electrically couple the individual circuit elements forming an integrated circuit. These interconnect levels are typically separated by an insulating or dielectric film. Previously, a silicon oxide film was the most commonly used material for such dielectric films having dielectric constants( k ) near 4 0. However, as the feature size is continuously scaling down, the relatively high k of such silicon oxide films became inadequate to provide efficient electrical insulation. As such, there has been an increasing market demand for materials with even lower dielectric constant for Interlayer Dielectric(ILD) applications, yet retaining thermal and mechanical integrity. We wish to report here our investigations on the preparation of ultra low k ILD materials using a sacrificial approach whereby organic groups are burnt out to generate low k porous ORMOSIL films. We have been able to prepare a variety of organically modified silicone resins leading to highly microporous thin films, exhibiting ultra low k from 1 80 to 2 87, and good to high modulus, 1 5 to 5 5 GPa. Structure property influences on porosity, dielectric constant and modulus will be discussed.

Photorefractivity in a Bi-functional Polymer Nanocomposites Sensitized by CdS Nanoparticle

We report an organic/inorganic hybridized nanocomposite consisting of a bi-functional poly（N-vinyl）-3-[p-nitrophenylazo]carbazolyl serves as a polymeric charge-transporting and second-order nonliner optical matrix, and CdS nanoparticles as photosensitizers to manifest photorefractive （PR） effect. The unpoled PVNPAK film exhibits a second harmonic generation （SHG） coefficient of 4.7 pm/V due to the possibility of self-alignment of the azo chromophore. Significant enhancement of photoconductivity is noticed with the increase of CdS nanoparticles concentration. The photorefractive property of the polymer nanocomposites were determined by two-beam coupling （TBC） experiment. The TBC gain and diffraction efficiency of 11.89 cm-1 and 3.2% were obtained for PVNPAK/CdS at zero electrical field.

Photoconductivity of novel poly(N-vinyl)-3-[p-nitrophenylazo]carbazole/CdS-nanoparticle polymer composite

The photoconductive characteristic of the inorganic/organic hybridized polymer system is reported, in which a novel bi-functional photorefractive (PR) poly(N-vinyl)-3-[p-nitrophenylazo]carbazole (PVNPAK) serves as a polymeric charge-transporting and second-order nonliner optical matrix and quantum dots composed of surface passivated cadmium sulfide serve as a charge-generation sensitizer. The hybrid PVNPAK/CdS-nanoparticles polymer composites with different mass ratio of CdS to PVNPAK were prepared. The generation of photocurrent on illumination and photoconductive properties of the PVNPAK/CdS-nanoparticles polymer composites were studied. The results show that the addition of CdS nanoparticle as a photosensitizer can enhance the photoconductivity of the PVNPAK significantly because of the properties of the high quantum efficiency of photosensitization and high charge transport to conducting polymer.

Inorganic-Organic Hybrid 18-Molybdodiphosphate Nanoparticles Bulk-modified Carbon Paste Electrode and Its Electrocatalysis

A kind of inorganic organic hybrid 18 molybdodiphosphate nanoparticles ([(C 4H 9) 4N] 6P 2Mo 18 O 62 ·4H 2O) was firstly used as a bulk modifier to fabricate a three dimensional chemically modified carbon paste electrode (CPE) by direct mixing. The electrochemical behavior of the solid nanoparticles dispersed in the CPE in acidic aqueous solution was characterized by cyclic and square wave voltammetry. The hybrid 18 molybdodiphosphate nanoparticles bulk modified CPE (MNP CPE) displayed a high electrocatalytic activity towards the reduction of nitrite, bromate and hydrogen peroxide. The remarkable advantages of the MNP CPE over the traditional polyoxometalates modified electrodes are their excellent reproducibility of surface renewal and high stability owing to the insolubility of the hybrid 18 molybdodiphosphate nanoparticles.

ORGANIC/INORGANIC HYBRID EPOXY NANOCOMPOSITES BASED ON OCTA(AMINOPHENYL)SILSESQUIOXANE

Octa（aminophenyl）silsesquioxane （OAPS） was used as the curing agent of diglycidyl ether of bisphenol-A （DGEBA） epoxy resin. A study on comparison of DGEBA/OAPS with DGEBA/4,4＇-diaminodiphenyl sulfone （DDS） epoxy resins was achieved. Differential scanning calorimetry was used to investigate the curing reaction and its kinetics, and the glass transition of DGEBA/OAPS. Thermogravimetric analysis was used to investigate thermal decomposition of the two kinds of epoxy resins. The reactions between amino groups and epoxy groups were investigated using Fourier transform infrared spectroscopy. Scanning electron microscopy was used to observe morphology of the two epoxy resins. The results indicated that OAPS had very good compatibility with DGEBA in molecular level, and could form a transparent DGEBA/OAPS resin. The curing reaction of the DGEBA/OAPS prepolymer could occur under low temperatures compared with DGEBA/DDS. The DGEBA/OAPS resin didn＇t exhibit glass transition, but the DGEBA/DDS did, which meant that the large cage structure of OAPS limited the motion of chains between the cross-linking points. Measurements of the contact angle indicated that the DGEBA/OAPS showed larger angles with water than the DGEBA/DDS resin. Thermogravimetric analysis indicated that the incorporation of OAPS into epoxy system resulted in low mass loss rate and high char yield, but its initial decomposition temperature seemed to be lowered.

Recent Advances and Progress for the Fabrication and Surface Modification of AIE-active Organic-inorganic Luminescent Composites

Organic dyes based hybrid organic-inorganic luminescent nanomaterials with high quantum efficiency, good physical or chemical stability, and favorable biocompatibility, have attracted growing attention recently because of their important applications in the areas of biomedical imaging, chemical sensors, and light-emitting diodes(LEDs). Nevertheless, conventional fluorescence molecules suffer from aggregation-caused quenching(ACQ) when they are doped into inorganic nanomaterials. Aggregation-induced emission(AIE) is an abnormal and intriguing fluorescent phenomenon that has aroused increasing interest for various applications especially in biomedical fields. Compared with conventional organic dyes, the AIE-active molecules will emit more intense fluorescence in their aggregates or solid states. It provides an elegant route to overcome the drawbacks of conventional organic molecules. Over the past few decades, the fabrication and surface modification of various organic-inorganic luminescent composites doped with AIE-active molecules have been reported. Therefore, it is highly desirable to summarize these advances. In this review, recent advances and progress in constructing various AIEgens-doped organic-inorganic hybrid nanocomposites and their subsequent surface modification were summarized. We hope this review could further promote the research of AIE-active functional materials.

A novel aptasensor based on 3D-inorganic hybrid composite as immobilized substrate for sensitive detection of platelet-derived growth factor

A novel electrochemical detection approach for platelet-derived growth factor（PDGF） via ＂sandwich＂structure is reported in this paper. 3D-4MgCO3 Mg（OH）2 4H2O-Au NPs inorganic hybrid composite was utilized as immobilized substrate for sensitive PDGF detection and Pt-Au bimetallic nanoparticles were labelled on PDGF aptamer to indirectly detect PDGF for the first time. The proposed aptasensor exhibited a high catalytic efficiency towards reduction of H2O2, hence the sensitive detection of PDGF was achieved.Results showed that the aptasensor exhibited excellent linear response to PDGF, in the range of 0.1 pg/m L–10 ng/m L（4 fmol/L–400 pmol/L）, with detection limit of 0.03 pg/m L（1.2 fmol/L）.

Photoelectrochemical Studies at CdS/PTTh Nanoparticles Interfaces

Photo-activities at Inorganic/Organic/Interfaces (IOI) consisting of CdS/ Polyterthiophine (PTTh) assemblies were investigated in nanoparticle suspension and in thin solid film forms. The effects PTTh modifier cause on the photoelec-trochemical behavior of the IOI were investigated using [Fe(CN)6]4- as photoactive hydrated electron donor agent. Results show that the adsorption process of [Fe(CN)6]3- (photolysis product) control the photoactivity outcome of IOI assemblies. CdS/PTTh shows lower heterogeneous photochemical response than native CdS. Native CdS amorphous nanoparticles adsorb more [Fe(CN)6]3- with very steady adsorption /desorption process than the modified ones. The interface activities were explained by analyzing the IOI junctions’ characteristics, such as electron affinity, work function and hole/electrons barrier heights. The aqueous nano-systems retained moderate stability as indicated by the reproducibility of their photocatalytic activities. Both [Fe(CN)6]4- and PTTh contributed to the stability of native CdS surfaces.

A Novel Inorganic-Organic Composite Constructed from Cobalt（Ⅱ）-Monosubstituted Polyoxometalates and Poly（amidoamine）-NH2 Dendrimers

An inorganic-organic composite was prepared by poly（amidoamine） （PAMAM） dendrimer reacting with cobalt（Ⅱ）-monosubstituted polyoxometalates Na5Co^Ⅱ（H2O）PW11O39 （PW11CO） in an aqueous solution. The hybrid composite PW11Co/PAMAM was characterized by FT-IR, UV-Vis diffuse reflectance spectra （DR-UV-Vis）, XPS, XRD and TG/DTA, indicating that the PWI iCo was chemically anchored to PAMAM. The morphologies of the title composite were characterized by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The catalytic activity was evaluated by oxidation of isobutyraldehyde （IBA） to isobutyric acid （IBAc） in MeCN under mild conditions （20 ℃, ambient pressure）, showing that the title compound is a more effective and recoverable catalyst than corresponding PW11Co.

Aqueous-Phase Sorption Behaviors of Cs⁺, Co²⁺, Sr²⁺and Cd²⁺ions on some Composite Ion Exchangers

A two new hybrid “organic-inorganic” composite ion exchangers (SAM and FAM), was synthesized by the combination of inorganic ion exchanger tin (IV) silicate and tin (IV) antimonate respectively with organic polymer polyacrylamide (PAm). The sorption isotherms for Cs+, Co2+, Sr2+ and Cd2+ ions on composite ion exchanger were investigated in the range (0.0005 - 0.01M) at different reaction temperature (30℃, 45℃ and 60℃ ± 1℃). The sorption data were subjected to different sorption isotherms and the results verified that Langmuir isotherm is the best model to be applied, and the monolayer sorption capacity were calculated and was found to increase as the reaction temperature increases.

Inorganic Nanotube/Organic Nanoparticle Hybrids for Enhanced Photoelectrochemical Properties

Inorganic/organic nanohybrids composed of arrayed TiO_2 nanotubes（Ti NTs）/porphyrin nanoparticles（NPs） have been fabricated via a wet chemical approach. The inorganic component, particularly the arrayed one-dimensional（1D） nanostructures, provides high charge-carrier mobility and rapid charge transport. The organic component exhibits extensive visible light absorption and good solution processability. Additionally, the geometric restraint by supramolecular assembly renders an improved photostability. A combination of these two components could thus allow for an efficient solar energy conversion. In this work, a colloid of porphyrin NPs prepared by a solvent exchange method is coated on anodic Ti NTs by means of a dip-coating treatment to form inorganic/organic hybrids. The hybrids exhibit an improvement on solar absorption and a significant enhancement on photocurrent generation at a small bias compared with individual component. Herein, the inorganic/organic nanohybrids are proved to be excellent photoanodes highly responsive to visible light and thus pave a way to discover new inorganic/organic assemblies for high-performance optoelectronic applications, as well as for device integration.

有机无机复合锂离子电池固态电解质专利分析

随着新能源汽车产业的飞速发展,传统液态电解质已经不能满足市场需求,固态电解质因其安全和能量密度优势已经成为未来发展的理想方向。然而由于无机电解质界面性能差和聚合物电解质材料离子电导率低的固有缺陷,严重阻碍了其实际应用,兼具无机电解质离子电导率高、力学性能好以及有机电解质柔韧性好且不与锂金属反应的复合体系固态电解质已经成为当前研究热点。为了解有机无机复合锂离子电池固态电解质发展态势,本文基于智慧芽Patsnap专利数据库检索结果,总结了全球及中国专利申请数量变化趋势和法律状态,对比了专利主要来源国和主要申请人情况,梳理了技术手段和技术效果之间的关系,重点从有机、无机、添加剂等材料组成,物理共混、三维、多层等复合方式以及特定制备工艺三个维度总结分析了专利技术发展情况。研究发现,我国在有机无机复合锂离子电池固态电解质专利布局方面具有数量优势,但目前申请人较为分散,且技术保护更多限于材料本身,建议加强合作交流,以及对上下游产业的整体技术保护,技术发展方向方面,高无机相用量的三维复合体系具有更佳的综合性能,但从产业化角度,聚合物填充无机颗粒体系可能发展得更快。

无机纳米颗粒及界面层协同改善倍增型近红外有机光电探测器性能

近红外有机光电探测器具有低成本、可溶液旋涂、生物兼容性好和柔性可穿戴等优势,在生物传感、医学成像、柔性可穿戴电子器件等领域有广泛的应用前景。倍增型有机光电探测器相比于二极管型有机光电探测器,因其具有更高的外量子效率(EQE>100%)和灵敏度而备受关注。该类器件利用电极附近被载流子陷阱捕获的一种载流子能辅助另一种极性相反的载流子从外电路隧穿注入到活性层中,实现光电倍增,但陷阱的数量在一定程度上会影响器件性能的进一步提升。本文通过在活性层中掺入无机ZnO纳米颗粒来增加电子陷阱数量,使得器件在反向偏压保持暗电流密度的前提下,亮电流密度得到提高。通过优化,发现当ZnO纳米颗粒掺杂比例为5%时性能最优,在850 nm LED照射、-15 V偏压下,与未掺杂ZnO纳米颗粒器件相比,亮电流密度提升了7.4倍。在此基础上,本文协同Al_(2)O_(3)界面修饰层,进一步改善器件性能。结果表明,Al_(2)O_(3)界面修饰层的插入可改善器件的阳极界面接触特性,使得器件在正向和反向偏压下都能够实现光响应。Al_(2)O_(3)修饰后的器件在15 V偏压、全光谱范围内,EQE最高可达10^(5)%,R最高达10^(4) A/W。本工作为高灵敏度有机光电探测器的发展提供了新的思路和方法。

饮用水处理过程中天然有机物引起的超滤膜污染机制研究进展

天然有机物(NOM)存在于地表水、地下水和土壤水中。超滤(UF)膜技术具有运行压力小、设备集成化程度高和占地面积小等优势,但NOM造成的复合污染使超滤膜在水处理的应用管理变得复杂。本文在概述NOM的来源、组成和化学性质的基础上,通过分析不同结构特征的NOM间的相互作用机制,阐述了不同结构特征的NOM的复合膜污染。从离子与NOM络合的影响因素、络合对NOM理化性质的影响等,分析了离子与NOM的复合膜污染。最后,分析了目前研究面临的挑战,并对未来的发展方向进行了展望。

旱作区农田土壤AM真菌对长期有机无机施肥的响应

AM真菌群落动态变化对于长期有效的土壤生态系统管理非常重要。为揭示旱作区农田土壤丛枝菌根(AM)真菌对长期有机、无机培肥管理的响应机制,利用单因素随机区组设计,基于连续11年的定位试验及高通量测序方法,研究了不施肥(T0)、长期单施化肥(T1)、长期化肥与牛粪有机肥(T2)和长期化肥与羊粪有机肥(T3)对土壤的影响,比较了土壤AM真菌群落组成及多样性间的差异,探究了驱动土壤AM真菌群落组成及多样性变化的土壤环境因子及其相互作用效应。结果表明:随培肥时间延长,与T0处理相比,T2、T3处理的土壤全氮、有机质含量显著增加,pH显著下降(P<0.05);与2018年相比,2021年的T0、T1和T3处理土壤全磷和速效钾含量显著下降。有机无机肥配施下,球囊霉属(Glomus)和类球囊霉属(Paraglomus)是土壤AM真菌的优势属,但近明球囊霉属(Claroideoglomus)的相对丰度显著下降,从优势属变为非优势属。近明球囊霉属较球囊霉属和类球囊霉属相对丰度而言,更容易受长期培肥影响而发生显著改变。连续有机无机肥配施到2018年后,T2、T3处理的土壤近明球囊霉属和两性球囊霉属(Ambispora)的相对丰度与T0间有显著差异(P<0.05);培肥至2021年后,T2、T3处理土壤近明球囊霉属和两性球囊霉属的相对丰度与T0处理间无显著差异。随培肥时间延长,不同处理间土壤AM真菌群落的α多样性差异消失。NMDS分析结果表明:长期培肥改变了土壤AM真菌群落的β多样性,但T2与T3处理间土壤AM真菌群落相似性较一致。连续培肥改变了土壤AM真菌群落结构组成和多样性,驱动AM真菌群落变化的土壤环境因子由土壤全氮、pH转变为土壤全磷。长期有机无机培肥没有同步提升土壤全磷、速效钾等主要理化性状。随培肥年限增加,驱动土壤AM真菌群落结构和多样性变化的土壤因子发生了显著改变,AM真菌群落会随土壤环境因子的变化倾向于更加敏感的驱动因子。

磷石膏的疏水改性研究现状及进展

磷石膏是湿法生产磷酸排放的固体废弃物,每生产1 t磷酸就会排出约5 t磷石膏。磷石膏表面具有亲水性,在高湿度环境下或接触水分之后易出现溶融蠕变效应,对力学性能造成负面影响,限制了其在建筑材料领域中的应用。全面综述了3种制备疏水磷石膏基材料的方法:表面疏水涂层、内掺疏水剂、有机/无机复合。通过比较各方法的优缺点,发现有机/无机复合能整体提高磷石膏基材料的疏水性和力学性能。

碳纤维增强树脂基复合材料的层间颗粒增韧技术研究进展

碳纤维增强树脂基复合材料(CFRP)具有高强高模的优点,被广泛应用于汽车、体育、船舶、航空航天等领域,达到了材料轻量化的要求。目前使用较多的树脂基体以环氧树脂(EP)等热固性树脂为代表,普遍存在脆性大、韧性差的问题,导致复合材料层合板容易在层间发生开裂。层间增韧是一种有效的增韧方式,它可以在不改变基体树脂粘度的情况下对特定区域进行增韧,提高材料的断裂韧性。本文介绍了层间断裂模式并总结了层间断裂韧性(ILFT)测试的数据处理方法,总结了聚合物颗粒与无机纳米颗粒(主要是碳纳米管)的颗粒种类、增韧机制、引入方式,并主要通过层间断裂韧性评价了各种颗粒的增韧效果。

MoO_(2)-NC/聚偏氟乙烯复合材料的制备及其电磁屏蔽性能

现代电子信息技术的飞速发展给人类生活带来巨大便利的同时也产生了严重的电磁干扰问题,不仅会影响电子设备的正常使用,而且还会危害人类健康。鉴于此,亟需开发高性能电磁屏蔽材料来解决电磁辐射污染。本文结合简单的水热法、原位化学氧化聚合和高温碳化工艺成功制备出一维异质纳米填料MoO_(2)-NC,并将其填充于柔性聚偏氟乙烯(PVDF)基体中,通过简单的溶液混合和热压技术制备出一系列MoO_(2)-NC不同质量分数下的MoO_(2)-NC/PVDF复合材料,研究了复合材料整体的电磁屏蔽性能。结果表明,经高温处理后,将前驱体聚吡咯(PPy)热解为碳材料,同时通过碳热还原法将MoO3还原成MoO_(2),使得纳米填料的电导率获得大幅提升,MoO_(2)-NC的电导率在20 MPa下最高能达到133.67 S/cm,比煅烧前的样品增加了28倍。当MoO_(2)-NC的质量分数为40%时,复合材料具有优异的电磁屏蔽性能,这一复合物的总屏蔽效能在X波段范围内最高能达到32.2 dB,比商用标准(20 dB)高出60%,由此表明MoO_(2)-NC具有作为高效电磁屏蔽功能填料的应用潜力。