联系人： 杨槐馨 研究员

报告摘要：
This report covers the hydrothermal crystallisation of transition-metal oxides and fluorides, focusing on the preparation of complex structures with unique physical properties (electronic and magnetic) and catalytic potential via mild solution chemistry. Using ruthenium and iridium oxides as examples, it demonstrates control over metal oxidation states and the formation of new structures. The Ru(VII) precursor KRuO4 enables the synthesis of Ru(V)-containing materials unattainable by conventional solid-state methods, such as SrRu2O6 (a high-temperature antiferromagnet) and Ba2Ru3O9(OH) (an oxyhydroxide). In situ neutron scattering reveals formation pathways involving Ru(VI) intermediates. The structures of SrRuO3(OH)2 and Sr3Ru2O8(OH)2 were solved using 3D electron diffraction and Rietveld analysis. In the domain of transition-metal fluorides, new materials were obtained via solvothermal routes from simple salts. Ni(OH)F exhibits antiferromagnetic ordering with symmetry-allowed ferromagnetic canting arising from partial anion ordering. The perovskites NaFeF3 and NaCoF3 show magnetic order dependent on t2g orbital occupancy. Na2CuF4 features one-dimensional chains of [CuF6] octahedra; pressure induces a reorientation of the Jahn-Teller axes. Metastable cubic CsMnF3 forms from solution and transforms to the hexagonal polymorph upon heating. This underscores the potential of fluoride solid-state chemistry for exploring diverse physical properties.

报告人简介：
Richard Walton is Professor of Chemistry at the University of Warwick, UK, and Deputy Head of Department. He studied Chemistry at Oxford and earned his PhD from Reading in 1997. Following postdoctoral research at Oxford on synchrotron and neutron diffraction methods, he held academic posts at Exeter and the Open University before joining Warwick in 2006. His research focuses on inorganic materials synthesis and structural characterisation, emphasising new hydrothermal and solvothermal routes to extended solid-state structures-including nanoporous zeotypes, MOFs, and complex oxides. A key aspect is developing in situ methods using international synchrotron and neutron facilities to track crystallisation and reactivity. His materials discovery work has led to industrial collaborations, including with Johnson Matthey (Royal Society Industry Fellow 2015–2019), developing heterogeneous catalysts. He has also led international projects with Brazil and Indonesia exploring materials for sustainability applications.