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Lecture

WEB First Gas-Phase Conversion of Heterotrimetallic Alkoxides to Multifunctional Complex Oxides

Thursday (24.09.2020)
15:15 - 15:30 Z: Special Symposia I
Part of:


The entire demystification of dynamic complex systems with emergent properties far from thermodynamic equilibrium like spontaneous self-organization of molecules in nature to construct complex cell architectures with specified functions represents one of the most fascinating and challenging multidisciplinary subjects of natural science. In analogy to elegant design principle in nature, the global materials genome project was initiated to accelerate the ambitious development of novel functional materials, system designs, and manufacturing methods to guide the creation of new high-performance materials towards sustainable innovations. We present an unprecedent synthetic methodology of volatile heterotrimetallic molecule with the general formula [SnFeLn(OtBu)8] (Ln = La, Pr). The molecular structure and decomposition properties were unambiguous investigated by X-ray analysis, mass spectrometry and thermogravimetric measurements that revealed the strong covalent connectivity of the heterogenic trinuclear alkoxy framework consist of one main group, transition and rare earth metal. Thermal decomposition experiments from the solid-state under nitrogen showed the formation of metallic Sn, SnO2, Fe3O4 and pyrochlore Sn2La2O7 in a single step at low temperatures. In contrast, the phase evolution under hydrolytic sol-gel conditions revealed the selective crystallization of strongly disordered pyrochlore with smaller lattice constants compared to the stoichiometric compound. The direct integration of the complex composite material onto transparent electrodes and sensor platforms were achieved by chemical vapor depositions, which revealed the strong interdependence of precursor and substrate temperature on the phase evolution, elemental stoichiometry and film morphology. The potential for nature-inspired application like gas sensing (smelling/nose), oxygen storage capacity (breathing/lung) and photoelectrochemical water splitting (photosynthesis/leaf) will be demonstrated.

Speaker:
David Graf
University of Cologne