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The symposium, Hybrid Colloids, Interfaces, and Nanomaterials was held as part of the 238th National ACS Meeting. The symposium brought scientists and engineers from both academia and industries together to report on recent advances and future directions in the emerging area of hybrid materials. The symposium focused on the fundamental issues of interfacing and integration of different material groups to achieve enhanced properties and performance. The combinations of material groups include inorganic-organic, inorganic-polymer, and synthetic-biological polymers. Over 90 papers were presented in 7 sessions in five days. 14 papers were invited contributions. The 7 sessions are: synthesis and functionalization, porous hybrids, self-assembly and patterning, interfacial characterization, biocolloids, biomineralization, template crystallization, and catalytic and energetic materials. The total attendance for this symposium is estimated to be 200. The research presented is relevant to colloids and interfacial science, polymer science, materials synthesis and characterization, separation, and catalysis.

The symposium disseminated and enhanced research relevant to the petroleum and energy fields. Most participants are researchers in the polymer, chemical, and materials research areas working on colloidal and interfacial aspects of hybrid materials. One concentration area is in template synthesis of organic materials on inorganic templates such as mesoporous silica or vice versa. Another concentration area is in surface science in which advances in mesoporous materials characterization by AFM and XPS were discussed. The third concentration area is in materials science where new hybrid materials are synthesized and characterized for energy storage and conversion.

This is the first time that this symposium was offered at the ACS Meeting sponsored by the COLL Division.

The funds were used to supplement the travel costs of foreign speakers to attend the conference. The abstracts of the authors supported by the funds are described below.

Dr. Helmut Schlaad from the Max Planck Institute of Colloids and Interfaces Germany gave a presentation entitled “Twisting amphiphilicity Yields “Sticky” Supramolecular Cones”. Hierarchical molecular self-assembly holds great promise in advancing science and technology. Amphiphiles define one of the most fundamental self-assembling molecules and have long found use in constructing discrete mesostructures, e.g. micelles and vesicles, for nanotechnology and biomedical applications. As geometry is well-known to have a strong influence on nanomaterial properties and higher-hierarchy self-assembly is critical for advanced technological applications, the amphiphile self-assemblies - despite tunability - is generally limited to highly symmetric spheroids and cylinders with uniform diameters, and little is known regarding the higher hierarchy self-assembly paradigm. We report that an intriguing twist on amphiphile design yields “sticky” supramolecular cones that extend amphiphilicity to the higherhierarchy self-assembly paradigm. An intriguing nucleation and growth-from-the-base pathway was found to generate the unprecedented angular cone geometry with a broken symmetry between the apex and base. Such suparmolecular cones demonstrate an interesting “stickiness” property at the base that enables base-to-base adhesion, leading to higher-hierarchy strings of the cones. Moreover, we show that the apex angle, length, as well as the “stickiness” of the supramolecular cones can all be tuned by chemical manipulations.

Dr. Cristina Giordano from the Max Planck Institute of Colloids and Inrterfaces Germany gave a presenation entitled "Synthesis of Fe3C nanostructures by a simple chemical route". Despite the actual and fundamental importance of iron-carbon nanostructures, the discovery that they possess very special features which makes materials derived thereof very attractive does not belong to the modern time. Metallurgy with iron carbides dates back to prehistory, when the iron of meteorites was used for a variety of purposes. In fact, iron carbide possesses superior magnetic properties, an improved thermal stability and higher resistance against oxidation processes as compared to elemental Fe, which is hardly appreciated. Recently, we have produced various Fe3C-nanostructures by a novel medium temperature (T= 800°C) reduction/carbidization process. In this process, the iron precursor reacts with an opportune nitrogen rich carbon source to form Fe3C nanoparticles enwrapped in single nano-filaments (fibres) of carbon. Chemical functionalisation of these shells by standard techniques enables the addressing of various hybrid-materials such as Fe3C@polymers. The combination of these materials has potential applications in nanomagnetism and catalysis due to their special features such as being robust against oxidation.

Dr. Hans Kühnle from the Max Planck Institute of Colloids and Interfaces Germany gave a presentation entitled "Programmable self-assembly of polymer-peptide conjugates". The conjugation of synthetic polymers to monomer-sequence defined peptides results in a class of multifunctional AB-block copolymers. Polymer-peptide conjugates proved to allow the transfer of biological organization principles toward polymer science. For instance, structure formation can be driven in various synthetic polymers via the peptideguided organization route. The organization principles, evident in bioconjugates, can be controlled by introducing a “chemical” switch concept in which pH-change triggers the self-assembly process. For that, temporary structure defects (switch-esters) are introduced into the peptide backbone to suppress the assembly behavior of the bioconjugate. An alternative approach to temporarily suppress aggregation behavior of bioconjugates is the BioSwitch method. This relies on the introduction of phosphate-moieties to side-chains of certain residues in the peptide aggregator domain. The side-chain modifications result in an effective suppression of the aggregation. The native peptide function can be restored by enzymatic dephosphorylation, which can be used to trigger the self-assembly process.