http://www.mdpi.com/journal/materials/special_issues/hybrid-materials/ Dear Colleagues, Research on functional hybrid materials has become one of the most rapidly developing fields of materials chemistry. In its most basic sense, a hybrid material is obtained by combining at least two components, commonly inorganic and organic, at the nanometer scale. Methods to synthesize inorganic-organic hybrid materials are often based on soft chemistry approaches, such as sol-gel processes, intercalation, exchange, or grafting. Considering the variety of combinations of components (and properties), inorganic-organic hybrids represent an intriguing class of materials with a large spectrum of applications. This special issue of Materials focuses on the synthesis of functional inorganic-organic hybrid materials, on the elucidation of structure-property relationships, as well as on the organization of hybrid building blocks on the micro- and macroscopic scale. Dr. Dominik Brühwiler Guest Editor Submission All papers should be submitted to materials@mdpi.com. To be published continuously until the deadline and papers will be listed together at the special website. Submitted papers should not have been published previously, nor be under consideration for publication elsewhere. All papers are refereed through a peer-review process. A guide for authors is available on the Instructions for Authors page. Materials is an international peer-reviewed quarterly journal published by MDPI. Review manuscripts: Before writing their manuscripts, potential authors of review articles should forward the title and a short abstract to materials@mdpi.com. We will then provide feedback on the suitability of the topic. Article Processing Charges (APC) Article Processing Charges (APC) will be waived for well prepared manuscripts of invited papers. For the first two volumes of this new journal the APC are of 300 CHF (or 550 CHF per paper for those papers that require extensive additional formatting and/or English corrections). http://www.mdpi.com/1996-1944/3/5/3141/ In the case of mixed-valence systems whose spin states are situated in the spin crossover region, new types of conjugated phenomena coupled with spin and charge are expected. From this viewpoint, we have investigated the multifunctional properties coupled with spin, charge and photon for the organic-inorganic hybrid system, A[FeIIFeIIIX3](A = (n-CnH2n+1)4N, spiropyran; X = dto(C2O2S2), tto(C2OS3), mto(C2O3S)). A[FeIIFeIII(dto)3] and A[FeIIFeIII(tto)3] undergo the ferromagnetic phase transitions, while A[FeIIFeIII(mto)3] undergoes a ferrimagnetic transition. In (n-CnH2n+1)4N [FeIIFeIII(dto)3](n = 3,4), a new type of phase transition called charge transfer phase transition (CTPT) takes place around 120 K, where the thermally induced charge transfer between FeII and FeIII occurs reversibly. At the CTPT, the iron valence state dynamically fluctuated with a frequency of about 0.1 MHz, which was confirmed by means of muon spin relaxation. The charge transfer phase transition and the ferromagnetic transition for (n-CnH2n+1)4N[FeIIFeIII(dto)3] remarkably depend on the size of intercalated cation. In the case of (SP)[FeIIFeIII(dto)3](SP = spiropyran), the photoinduced isomerization of SP under UV irradiation induces the charge transfer phase transition in the [FeIIFeIII(dto)3] layer and the remarkable change of the ferromagnetic transition temperature. In the case of (n-CnH2n+1)4N[FeIIFeIII(mto)3](mto = C2O3S), a rapid spin equilibrium between the high-spin state (S = 5/2) and the low-spin state (S = 1/2) at the FeIIIO3S3 site takes place in a wide temperature range, which induces the valence fluctuation of the FeS3O3 and FeO6 sites through the ferromagnetic coupling between the low spin state (S = 1/2) of the FeIIIS3O3 site and the high spin state (S = 2) of the FeIIO6 site. http://www.mdpi.com/1996-1944/3/5/3141/ Tue, 11 May 2010 00:00:00 CEST Materials 2010-05-11 3 5 Review 3141 3187 1996-1944 Progress of Multi Functional Properties of Organic-Inorganic Hybrid System, A[FeIIFeIIIX3] (A = (n-CnH2n+1)4N, Spiropyran; X = C2O2S2, C2OS3, C2O3S) 2010-05-11 doi: 10.3390/ma3053141 Kojima Enomoto Kida Kagesawa http://www.mdpi.com/1996-1944/3/3/1981/ Organic/inorganic nanohybrid materials have attracted particular scientific and technological interest because they combine the properties of the organic and the inorganic component. Inorganic nanoparticles exhibit interesting electrical, optical, magnetic and/or catalytic properties, which are related with their nano-scale dimensions. However, their high surface-to-volume ratio often induces agglomeration and leads to the loss of their attractive properties. Surface modification of the inorganic nano-objects with physically or chemically end-tethered polymer chains has been employed to overcome this problem. Covalent tethered polymer chains are realized by three different approaches: the “grafting to”, the “grafting from” and the “grafting through” method. This article reviews the synthesis of end-grafted polymer chains onto inorganic nanoparticles using “controlled/living” polymerization techniques, which allow control over the polymer characteristics and the grafting density of the end-tethered polymer chains. http://www.mdpi.com/1996-1944/3/3/1981/ Thu, 18 Mar 2010 00:00:00 CET Materials 2010-03-18 3 3 Review 1981 2026 1996-1944 End-Grafted Polymer Chains onto Inorganic Nano-Objects 2010-03-18 doi: 10.3390/ma3031981 Achilleos Vamvakaki http://www.mdpi.com/1996-1944/3/3/1782/ A review of recent progress in hybrid integrated platforms for silicon photonics is presented. Integration of III-V semiconductors onto silicon-on-insulator substrates based on two different bonding techniques is compared, one comprising only inorganic materials, the other technique using an organic bonding agent. Issues such as bonding process and mechanism, bonding strength, uniformity, wafer surface requirement, and stress distribution are studied in detail. The application in silicon photonics to realize high-performance active and passive photonic devices on low-cost silicon wafers is discussed. Hybrid integration is believed to be a promising technology in a variety of applications of silicon photonics. http://www.mdpi.com/1996-1944/3/3/1782/ Fri, 12 Mar 2010 00:00:00 CET Materials 2010-03-12 3 3 Review 1782 1802 1996-1944 Hybrid Integrated Platforms for Silicon Photonics 2010-03-12 doi: 10.3390/ma3031782 Liang Roelkens Baets Bowers http://www.mdpi.com/1996-1944/3/2/1302/ A layer-by-layer method has been developed for the synthesis of metal-organic frameworks (MOFs) and their deposition on functionalized organic surfaces. The approach is based on the sequential immersion of functionalized organic surfaces into solutions of the building blocks of the MOF, i.e., the organic ligand and the inorganic unit. The synthesis and growth of different types of MOFs on substrates with different functionalization, like COOH, OH and pyridine terminated surfaces, were studied and characterized with different surface characterization techniques. A controlled and highly oriented growth of very homogenous films was obtained using this method. The layer-by-layer method offered also the possibility to study the kinetics of film formation in more detail using surface plasmon resonance and quartz crystal microbalance. In addition, this method demonstrates the potential to synthesize new classes of MOFs not accessible by conventional methods. Finally, the controlled growth of MOF thin films is important for many applications like chemical sensors, membranes and related electrodes. http://www.mdpi.com/1996-1944/3/2/1302/ Tue, 23 Feb 2010 00:00:00 CET Materials 2010-02-23 3 2 Article 1302 1315 1996-1944 Layer-by-Layer Method for the Synthesis and Growth of Surface Mounted Metal-Organic Frameworks (SURMOFs) 2010-02-23 doi: 10.3390/ma3021302 Osama Shekhah http://www.mdpi.com/1996-1944/3/2/1281/ Correlative studies of three oxalato-bridged polymers, obtained under hydrothermal conditions for the two isostructural compounds {Rb(HC2O4)(H2C2O4)(H2O)2}∞1, 1, {H3O(HC2O4)(H2C2O4).2H2O}∞1, 2, and by conventional synthetic method for {Rb(HC2O4)}∞3, 3, allowed the identification of H-bond patterns and structural dimensionality. Ferroïc domain structures are confirmed by electric measurements performed on 3. Although 2 resembles one oxalic acid sesquihydrate, its structure determination doesn’t display any kind of disorder and leads to recognition of a supramolecular network identical to hybrid s-block series, where moreover, unusual H3O+ and NH4+ similarity is brought out. Thermal behaviors show that 1D frameworks with extended H-bonds, whether with or without a metal center, have the same stability. Inversely, despite the dimensionalities, the same metallic intermediate and final compounds are obtained for the two Rb+ ferroïc materials. http://www.mdpi.com/1996-1944/3/2/1281/ Tue, 23 Feb 2010 00:00:00 CET Materials 2010-02-23 3 2 Article 1281 1301 1996-1944 Synthesis, Structure and Thermal Behavior of Oxalato-Bridged Rb+ and H3O+ Extended Frameworks with Different Dimensionalities 2010-02-23 doi: 10.3390/ma3021281 Hamza Kherfi Malika Hamadène Achoura Guehria-Laïdoudi Slimane Dahaoui Claude Lecomte http://www.mdpi.com/1996-1944/3/1/158/ Inorganic-organic hybrid crystals containing α-octamolybdate (Mo8) or hexamolybdate (Mo6) were isolated by using hexadecyltrimethylammonium (C16) surfactant. The packing mode of the inorganic layers depended on a difference in the polyoxomolybdate molecular structure. The structure for both crystals consisted of alternate stacking of C16 organic bilayers and polyoxomolybdate inorganic layers with a periodicity of 24.4–24.6 Å. However, the C16-Mo8 crystals contained Mo8 monolayers, while the C16-Mo6 crystals contained Mo6 bilayers. These lattice structures for the polyoxometalate/organic hybrid will be designed by the molecular structures of polyoxometalate. http://www.mdpi.com/1996-1944/3/1/158/ Wed, 06 Jan 2010 00:00:00 CET Materials 2010-01-06 3 1 Article 158 164 1996-1944 Controllable Layered Structures in Polyoxomolybdate-Surfactant Hybrid Crystals 2010-01-06 doi: 10.3390/ma3010158 Takeru Ito Toshihiro Yamase