TU Delft Catalysis Engineering researchers strike two publications in Nature Communications in one month
In the first work, Goesten et al. report the surprising mechanism of formation of the well-known Metal Organic Framework UiO-66 in the presence of HCl. In this combined spectroscopic and theoretical approach the mechanism has been unfolded, and the chemistry is captivating; UiO-66’s crystallization is regulated by a phenomenon commonly referred to as a clock reaction. This type of reaction is famous for observable oscillations in species concentration in the liquid phase. In UiO-66’s case, oscillations show up both in size and geometry of the precipitating crystals; clock-like evolutions to equilibrium. It is the first time such phenomena have been shown to govern crystallization, but the authors suspect more MOFs to reproduce UiO-66’s swinging way to existence.
- M.G. Goesten, M.F de Lange, A. I. Olivos-Suarez, A.V. Bavykina, P. Serra-Crespo, C. Krywka, F.M. Bickelhaupt, F. Kapteijn and J. Gascon. Evidence for a chemical clock in oscillatory formation of UiO-66. Nature Commun. 7 (2016) 11832 doi:10.1038/ncomms11832
In the second work, led by Mark Koper’s team (Leiden University), iridium containing double perovskites are shown to display excellent electro-catalytic properties for the oxidation of water. The development of active, cost-effective and stable oxygen-evolving catalysts is one of the major challenges for solar-to-fuel conversion towards sustainable energy generation. Iridium oxide exhibits the best available compromise between catalytic activity and stability in acid media, but it is prohibitively expensive for large-scale applications. In this work, a class of oxygen-evolving catalysts is reported based on iridium double perovskites which contain 32 wt% less iridium than IrO2 and yet exhibit a more than threefold higher activity in acid media.
- O. Diaz-Morales, S. Raaijman, R. Kortlever, P. J. Kooyman, T. Wezendonk, J. Gascon, W.T. Fu and M. T. M. Koper. Iridium-based Double Perovskites for Efficient Water Oxidation in Acid Media. Nature Commun. 7 (2016) 12363 doi:10.1038/ncomms12363