| Autor: |
Brown AJ; School of Chemistry, The University of Sydney, Camperdown NSW, Sydney 2006, Australia., Miller LA; Research School of Earth Sciences, Australian National University, Canberra ACT 2601, Australia., Berry AJ; Research School of Earth Sciences, Australian National University, Canberra ACT 2601, Australia., Lewis W; School of Chemistry, The University of Sydney, Camperdown NSW, Sydney 2006, Australia.; Sydney Analytical, The University of Sydney, Camperdown NSW, Sydney 2006, Australia., Barnett C; School of Chemistry, The University of Sydney, Camperdown NSW, Sydney 2006, Australia., Yuen A; School of Chemistry, The University of Sydney, Camperdown NSW, Sydney 2006, Australia., Brennan MJ; School of Chemistry, The University of Sydney, Camperdown NSW, Sydney 2006, Australia., Auckett JE; Australian Synchrotron, Australian Nuclear Science and Technology Organisation, 800 Blackburn Road, Clayton 3168, Australia., Maynard-Casely HE; Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW 2232, Australia., Ling CD; School of Chemistry, The University of Sydney, Camperdown NSW, Sydney 2006, Australia. |
| Abstrakt: |
We have made the compound 2O-BaPtO 3 by high-pressure, high-temperature synthesis, determined its structure, and tested its catalytic activity. Compounds of the same stoichiometry have been reported and tentatively identified as hexagonal perovskites, and although no structural model was ever established, 2O-BaPtO 3 is clearly different and, to the best of our knowledge, unique. It features continuous chains of face-sharing PtO 6 octahedra, like the well-known 2H hexagonal perovskite type, but with a staggered offset between the chains that breaks hexagonal symmetry and disrupts the close-packed array of A = Ba and X = O that is a defining characteristic of ABX 3 perovskites. We investigated this structure and its stability vs the conventional 2H form using X-ray and neutron diffraction, X-ray absorption spectroscopy, and ab initio calculations. Catalytic testing of 2O-BaPtO 3 showed that it is active for hydrogen evolution. |
