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P-N junctions are of great importance both in modern electronic applications and in understanding other semiconductor devices. Organic/inorganic P-N junction nanowires composed of functional organic molecules and inorganic molecules may be able to realize new or improved chemical and physical properties that were not observed in the individual component on nanosize and their bulk materials. We report herein the fabrication of the organic/inorganic semiconductor P-N junction nanowire and the remarkable performance on the light-controlled diode within a single hybrid P-N junction nanowire. Controlling the conductivity of the P-N junction nanowire by the light irradiation simply to achieve diode work indicates a new way to realize the photoelectric integration in a single nanowire device.  相似文献   

3.
The current state of the hierarchical chemical functionalization of inorganic nanoparticles (NPs) by shell-by-shell (SbS)-assembly of organic layers around the NP cores is summarized. This supramolecular functionalization concept is based on two steps: 1) the covalent grafting of a first ligand–shell consisting of, for example, long chain phosphonic acids and 2) the noncovalent interdigitation of amphiphiles forming the second ligand shell. The latter process is guaranteed predominantly by solvophobic interactions. These highly order organic–inorganic hybrid architectures are currently an emerging field at the interface of synthetic chemistry, nanotechnology, and materials science. The doubly functionalized NPs display tunable materials properties, such a controlled dispersibility and stability in various solvents, highly efficient trapping of guest molecules in between the ligand shells (water cleaning) as well as compartmentalization and modification of electronic interactions between photoactive components integrated in such complex nano-architectures. Such SbS-functionalized NPs have a high potential as water-cleaning materials and also some first prototype applications as biomedicinal therapeutics have been presented.  相似文献   

4.
Molecular ferroelastics have received particular attention for potential applications in mechanical switches, shape memory, energy conversion, information processing, and solar cells, by taking advantages of their low-cost, light-weight, easy preparation, and mechanical flexibility. The unique structures of organic–inorganic hybrid perovskites have been considered to be a design platform for symmetry-breaking-associated order–disorder in lattice, thereby possessing great potential for ferroelastic phase transition. Herein, we review the research progress of organic–inorganic hybrid perovskite ferroelastics in recent years, focusing on the crystal structures, dimensions, phase transitions and ferroelastic properties. In view of the few reports on molecular-based hybrid ferroelastics, we look forward to the structural design strategies of molecular ferroelastic materials, as well as the opportunities and challenges faced by molecular-based hybrid ferroelastic materials in the future. This review will have positive guiding significance for the synthesis and future exploration of organic–inorganic hybrid molecular ferroelastics.  相似文献   

5.
Organic/inorganic hybrid materials prepared by the sol–gel approach have rapidly become a fascinating new field of research in materials science. The explosion of activity in this area in the past decade has made tremendous progress in both the fundamental understanding of the sol–gel process and the development and applications of new organic/inorganic hybrid materials. Polymer-inorganic nanocomposite present an interesting approach to improve the separation properties of polymer material because they possess properties of both organic and inorganic such as good permeability, selectivity, mechanical strength, and thermal and chemical stability. Composite material derived by combining the sol–gel approach and organic polymers synthesis of hybrid material were the focus area of review It has also been demonstrated in this review that a more complete understanding of their structure–property behavior can be gained by employing many of the standard tools that are utilized for developing similar structure–property relationships of organic polymers. This review article is introductory in nature and gives introduction to composite materials/nanocomposite, their applications and the methods commonly employed for their synthesis and characterization. A brief literature survey on the polysaccharide templated and polysaccharide/protein dual templated synthesis of silica composite materials is also presented in this review article.  相似文献   

6.
稀土配合物杂化发光材料的组装及光物理性质研究进展   总被引:1,自引:0,他引:1  
稀土配合物兼具无机物稳定性好以及有机物荧光量子效率高的优点,而且具有可设计性,制备简便,容易修饰,荧光性质优异(发射谱带窄、色纯度高、荧光寿命长、量子产率高以及发射光谱范围覆盖可见和近红外光区等).但配合物的光、热、化学稳定性和机械加工性能相对较差,因而限制了其在很多领域中的实际应用.近年来的研究表明,将稀土配合物引入到各种基质材料中可以改善其稳定性及机械加工性能,并对其光物理性质产生调制作用.根据基质材料的不同,杂化材料可分为无机基质、无机/有机复合基质及有机基质杂化材料.本文综述了这些不同基质稀土配合物杂化发光材料的研究进展,探讨了主客体间相互作用对杂化材料光物理性质及稳定性的影响,为实现稀土配合物杂化发光材料在光学器件领域(LED照明、光纤维、光学放大器及激光等)及生命分析领域的应用提供了重要的理论依据.  相似文献   

7.
The controlled synthesis of inorganic micro- and nanostructures with tailored morphologies and patterns has attracted intensive interest because the properties and performances of micro- and nanostructured materials are largely dependent on the shape and structure of the primary building blocks and the way in which the building blocks are assembled or integrated. This review summarizes the recent advances on the solution-phase synthesis of inorganic micro- and nanostructures with controlled morphologies and patterns via three typical colloidal chemical routes, i.e., synthesis based on catanionic micelles, reactive templates, and colloidal crystal templates, with focus on the approaches developed in our lab. Firstly, catanionic micelles formed by mixed cationic/anionic surfactants are used as effective reaction media for the shape-controlled synthesis of inorganic nanocrystals and the solution growth of hierarchical superstructures assembled by one-dimensional (1D) nanostructures. Secondly, reactive template-directed chemical transformation strategy provides a simple and versatile route to fabricate both hollow structures and 1D nanostructures. Thirdly, colloidal crystals are employed as very effective templates for the facile solution-phase synthesis of novel inorganic structures with controlled patterns, such as three-dimensionally (3D) ordered macroporous materials and two-dimensionally (2D) patterned nanoarrays and nanonets. Finally, a brief outlook on the future development in this area is presented.  相似文献   

8.
This paper gives an overview of weak aggregation due to long-range molecular forces beyond the first neighbor. Such subtle self-assemblies are an important part of modern colloidal chemistry and concern organic molecules as well as inorganic electrolytes and hybrid aggregates. Diverse aspects of such colloidal aggregations, as described in this special issue, can be characterized by the effective free energy per molecule involved. We discuss here expectations about emerging knowledge in this field and predictive modeling of inorganic as well as organic colloids and hybrid aggregates. Some still open questions are also given.  相似文献   

9.
This article presents a review of the colloidal and liquid-crystalline properties of vanadium pentoxide suspensions from a physicist's perspective. The processes occurring during the synthesis of these suspensions are first discussed. Then, the liquid-crystalline properties of V2O5 sols and gels are described. These nematic phases are easily aligned by weak magnetic fields or by alternative electric fields. The delicate interplay between repulsive hardcore and electrostatic interactions and van der Waals attractions defines the (concentration, ionic strength) phase diagram that includes an isotropic phase, a uniaxial nematic phase, a biaxial nematic gel state and a flocculated state. Deuterium NMR spectroscopy of D2O molecules gives information on the rotational dynamics of the nematic phase. Finally, various applications of these colloidal suspensions in the fields of hybrid organic/inorganic materials, mesoporous solids, and of the structures of biomolecules, are reviewed.  相似文献   

10.
Silica-based mesoporous organic-inorganic hybrid materials   总被引:8,自引:0,他引:8  
Mesoporous organic-inorganic hybrid materials, a new class of materials characterized by large specific surface areas and pore sizes between 2 and 15 nm, have been obtained through the coupling of inorganic and organic components by template synthesis. The incorporation of functionalities can be achieved in three ways: by subsequent attachment of organic components onto a pure silica matrix (grafting), by simultaneous reaction of condensable inorganic silica species and silylated organic compounds (co-condensation, one-pot synthesis), and by the use of bissilylated organic precursors that lead to periodic mesoporous organosilicas (PMOs). This Review gives an overview of the preparation, properties, and potential applications of these materials in the areas of catalysis, sorption, chromatography, and the construction of systems for controlled release of active compounds, as well as molecular switches, with the main focus being on PMOs.  相似文献   

11.
The efficiency of the extraction and removal of pollutants from food and the environment has been an important issue in analytical science. By incorporating inorganic species into an organic matrix, a new material known as an organic–inorganic hybrid material is formed. As it possesses high selectivity, permeability, and mechanical and chemical stabilities, organic–inorganic hybrid materials constitute an emerging research field and have become popular to serve as sorbents in various separaton science methods. Here, we review recent significant advances in analytical solid‐phase extraction employing organic–inorganic composite/nanocomposite sorbents for the extraction of organic and inorganic pollutants from various types of food and environmental matrices. The physicochemical characteristics, extraction properties, and analytical performances of sorbents are discussed; including morphology and surface characteristics, types of functional groups, interaction mechanism, selectivity and sensitivity, accuracy, and regeneration abilities. Organic–inorganic hybrid sorbents combined with extraction techniques are highly promising for sample preparation of various food and environmental matrixes with analytes at trace levels.  相似文献   

12.
Hybrid organic–inorganic materials have been considered as a new candidate in the field of thermoelectric materials since the last decade owing to their great potential to enhance the thermoelectric performance by utilizing the low thermal conductivity of organic materials and the high Seebeck coefficient, and high electrical conductivity of inorganic materials. Herein, we provide an overview of interfacial engineering in the synthesis of various organic–inorganic thermoelectric hybrid materials, along with the dimensional design for tuning their thermoelectric properties. Interfacial effects are examined in terms of nanostructures, physical properties, and chemical doping between the inorganic and organic components. Several key factors which dictate the thermoelectric efficiency and performance of various electronic devices are also discussed, such as the thermal conductivity, electric transportation, electronic band structures, and band convergence of the hybrid materials.  相似文献   

13.
Polymer solar cell (PSC) has been developed vastly in the past decade due to the advantages of low cost, lightweight, mechanical flexibility, versatility of chemical design and synthesis, semitransparency, and solution processing. The performance and lifetime of PSCs are highly dependent on the properties of both active materials and their interfaces. The combination of the versatility of organic chemistry and the multitude of well-understood ligand–metal interactions allows self-assembled monolayers (SAMs) of organic molecules to direct control over the electronic and chemical properties at the inorganic–organic interfaces. Thus, SAMs are an attractive pathway to reconcile interfaces with tunable interface properties in PSCs. Hence, this review describes the application of SAMs in PSCs at different interfaces. First, SAMs as alternatives of traditional transporting materials to reduce the barrier at indium tin oxide (ITO)/active layer interface due to the ability of tuning work function of ITO electrode are discussed. Second, the modifications of metal oxide by SAMs to control the electrical contacts at transporting layer/active layer interface are described. Third, tailoring the properties of the donor/acceptor interface by SAMs to improve the performance of PSCs are summarized. Finally, perspectives and challenges are pointed out for developing highly stable and high-performance PSCs by applying SAMs.  相似文献   

14.
Bridged polysilsesquioxanes (BPS) are a class of versatile functional hybrid materials with tunable chemical, physical and mechanical properties. This tutorial review describes recent advances of these functional hybrid nanomaterials. The review includes control of factors affecting nanometre scale morphology, the preparation of spherical hybrid nanoparticles, along with applications in fields including energy, optics and electronics. Special emphasis will be made regarding the synergy between the organic component of the hybrid material and the polysilsesquioxane moieties.  相似文献   

15.
The successful one-step preparation method of monodisperse hybrid silica particles was studied using organosilane chemicals in aqueous solution. In general, almost all of the hybrid silica materials were made by a complex method where organic materials were coated on the surface of silica substrate via chemical reaction. However, our novel method can be applied to prepare colloidal hybrid particles without using substrate material. This method has three advantages: (i) this simple method gives the opportunity to prepare hybrid particles with high monodispersity through the self-hydrolysis of various organosilane monomers in aqueous solution, (ii) this efficient method can be applied to load lots of organic functional groups on the surface of silica particles through a one-step preparation method using only organosilane, and (iii) this effective method can be used to control the particle size of the product by changing the experimental conditions such as the concentration of the precursor or the reaction temperature. Detailed characterization of the hybrid particles by scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis (TGA) was performed to elucidate the morphologies and properties of the hybrid silica particles.  相似文献   

16.
《Solid State Sciences》2000,2(3):313-334
The latest developments in inorganic membranes are closely related to recent advances in solid state science. Sol–gel processing, plasma-enhanced chemical vapor deposition and hydrothermal synthesis are methods that can be used for inorganic membrane preparation. Innovative concepts from material science (templating effect, nanophase materials, growing of continuous zeolite layers, hybrid organic–inorganic materials) have been applied by our group to the preparation of inorganic membrane materials. Sol–gel-derived nanophase ceramic membranes are presented with current applications in nanofiltration and catalytic membrane reactors. Silica membranes with an ordered porosity, due to liquid crystal phase templating effect, are described with potential application in pervaporation. Defect-free and thermally stable zeolite membranes can be obtained through an original synthesis method, in which zeolite crystals are grown inside the pores of a support. Hybrid organic–inorganic materials with permselective properties for gas separation and facilitated transport of solutes in liquid media, have been successfully adapted to membrane applications. Potential membrane developments offered by CVD deposition techniques are also illustrated through several examples related to the preparation of purely inorganic and hybrid organic–inorganic membrane materials.  相似文献   

17.
According to coordination chemistry principle and molecular assembly technology, series of ternary lanthanide centered hybrid systems have been constructed through coordination bonds. Among one component (ligand) is organically modified Si-O network, which originates from the functional molecular bridge (BFPPSi) by the functionalization of 1,3-bis(2-formylphenoxy)-2-propanol (BFPP) with 3-(triethoxysilyl)propyl isocyanate. In the second component (ligand), three different organic polymeric chains are introduced, poly-(methyl methacrylate) (PMMA, from the polymerization of MMA with the benzoyl peroxide [BPO] as the initiator), poly-(methyl acrylic acid) (PMAA, from the polymerization of MAA with the BPO as the initiator), polyvinyl pyridine, respectively. All these ternary hybrid materials show homogeneous, regular microstructure, suggesting the existence of assembly process of lanthanide centers, inorganic Si-O network and organic polymer chain. Compared to the binary hybrids without polymer chain, the photoluminescent properties of these ternary hybrids present stronger luminescent intensities, longer lifetimes and higher luminescent quantum efficiencies indicating that the introduction of organic polymer chain is favorable for the luminescence of the whole hybrid systems.  相似文献   

18.
The kinetics of photolysis of a styrylquinoline (SQ) derivative as the photochromic ligand in organic—inorganic hybrid nanosystems (HNSs) with the core composed of CdS quantum dots (QDs) has been studied for the first time as a function of the number of ligand molecules in the HNS shell, which varied from 1 to 10. The hybrid nanosystems have been synthesized in the microwave-assisted mode according to the single-step injection-free procedure. It has been shown that high quantum yields of photoisomerization of the SQ ligand are conserved in the HNS. In the early stages of the photolysis, regardless of the number of SQ ligand molecules in the HNS shell, the kinetics obeys the equation for the photolysis of the monomolecular system (model SQ photochrome) with allowance for the absorption due to QDs as an inert shutter. During the course of long-term photolysis, the quantum dots undergo photodegradation to be completely decomposed. According to the principal component analysis data, several photoproducts with different absorption spectra are formed at the intermediate times of the HNS photolysis.  相似文献   

19.
This critical review presents a discussion on the major advances in the field of organic-inorganic hybrid membranes for fuel cells application. The hybrid organic-inorganic approach, when the organic part is not conductive, reproduces to some extent the behavior of Nafion where discrete hydrophilic and hydrophilic domains are homogeneously distributed. A large variety of proton conducting or non conducting polymers can be combined with various functionalized, inorganic mesostructured particles or an inorganic network in order to achieve high proton conductivity, and good mechanical and chemical properties. The tuning of the interface between these two components and the control over chemical and processing conditions are the key parameters in fabricating these hybrid organic-inorganic membranes with a high degree of reproducibility. This dynamic coupling between chemistry and processing requires the extensive use and development of complementary ex situ measurements with in situ characterization techniques, following in real time the molecular precursor solutions to the formation of the final hybrid organic-inorganic membranes. These membranes combine the intrinsic physical and chemical properties of both the inorganic and organic components. The development of the sol-gel chemistry allows a fine tuning of the inorganic network, which exhibits acid-based functionalized pores (-SO(3)H, -PO(3)H(2), -COOH), tunable pore size and connectivity, high surface area and accessibility. As such, these hybrid membranes containing inorganic materials are a promising family for controlling conductivity, mechanical and chemical properties (349 references).  相似文献   

20.
The composition and structure of inorganic shells grown over CdSe semiconductor nanocrystal dots and rods were optimized to yield enhanced photoluminescence properties after ligand exchange followed by coating with phytochelatin-related peptides. We show that, in addition to the peptides imparting superior colloidal properties and providing biofunctionality in a single-step reaction, the improved shells and pretreatment with UV irradiation resulted in high quantum yields for the nanocrystals in water. Moreover, peptide coating caused a noticeable red-shift in the absorption and emission spectra for one of the tested shells, suggesting that exciton-molecular orbital (X-MO) coupling might take place in these hybrid inorganic-organic composite materials.  相似文献   

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