Metal-organic frameworks (MOFs) have attracted a great deal of attention over the past decade, due to the ability to systematically engineer desired chemical and physical properties in MOFs via modifications of the constituent building blocks. The PI will pursue two very different objectives in this proposal?crystal engineering of highly stable and porous MOFs for hydrogen storage and nano-engineering of MOFs for potential applications in templated synthesis of core-shell nanostructures and in biomedical imaging and drug delivery. In the first objective, isoreticular families of robust and highly porous MOFs based on both 4,4-connected PtS and 4,8-connected Scu topologies will be synthesized and evaluated for hydrogen uptake. By systematically tuning the size of the bridging ligands, ?aromatics-rich? microporous MOFs with different degrees of interpenetration will be obtained. Rigid guest molecules will be incorporated into MOFs to stabilize the frameworks, to increase microporous surface areas, and to enhance the MOF-hydrogen interactions. In the second objective, the PI proposes to continue fundamental studies on nanoscale MOFs (NMOFs) and explore their potential applications in a number of areas. Pioneering work from the PI?s lab has demonstrated the ability to scale-down MOFs to the nano-regime to generate a new class of highly tailorable hybrid nanomaterials with controllable compositions, sizes, size distributions, and morphologies. Further refinement of the synthetic methodologies will allow the design of novel hierarchically assembled core-shell nanostructures for potential photocatalytic proton reduction and water oxidation and the synthesis of novel biodegradable and biocompatible nanomaterials for magnetic resonance imaging, computed tomography, and drug delivery. The success of this research will not only have important impact on a renewable and sustainable future energy strategy, but also make positive contributions to improved human health.
NON-TECHNICAL SUMMARY: This DMR proposal aims at the rational synthesis of a new class of hybrid materials, namely metal-organic frameworks (MOFs), at both the bulk and nanometer scales. Systematic engineering of the bulk MOF materials will allow for the synthesis of new hydrogen storage materials which will enable hydrogen-based fuel cell technology for mobile power sources. Such hydrogen storage materials are of paramount importance not only to the national energy security but also to the reduction of environmental pollution. Scaling down of MOFs to the nanometer regime allows the synthesis of a new class of highly tailorable hybrid nanomaterials with controllable compositions, sizes, size distributions, and morphologies. Such nanoscale MOFs (NMOFs) will be used to template the synthesis of novel hierarchically assembled core-shell nanostructures for photocatalytic proton reduction and water oxidation, as well as for the synthesis of novel biodegradable and biocompatible nanomaterials for biological sensing, biomedical imaging, and drug delivery. The PI will also be actively involved in personnel training at multiple levels, including high school students, undergraduate students, graduate students, and postdoctoral research associates. The proposed research will thus significantly contribute to NSF?s mission on promoting and integrating research and education in addition to its potential impact on our nation?s future energy technologies and health care.
Metal-organic frameworks have attracted a great deal of attention in recent years, owing to their potential applications in many areas. In this proposal, we set out to pursue two objectives: crystal engineering of highly stable and porous MOFs for gas storage and nano-engineering of MOFs for applications in biomedical imaging and drug delivery. We have made significant progess in both objectives. Spefically, we have prepared a number of porous MOFs and measured their gas uptake capacities. We identified one of the 6,8-connected MOFs that has exceptional high methane uptake capacity. In the Nanoscale MOF research, we developed several distinct strategies for the synthesis of a variety of different NMOFs, and demonstrated their potential applications in magentic resonanace imaging, CT imaging, and optical imaging. We have also shown that NMOFs can be used to deliver a number of anticancer drugs, such as cisplatin, methotrexate, bisphosphnates, and even biologics such as small interfering RNAs. The preclinical studies for NMOFs in imaging and cancer therapy have been ongoing in the PI's lab, with encouraging in vivo results emerging in the past couple of years. This project has thus made impirtant contributions to the development of renewable and sustainable energy technologies but also to the imrpovement of human health. The funding also allows the PI to train a large number of graduate students, postdoctoral fellows, undergraduate students, and high school students in highly interdisciplinary molecular materials research.
