TY - JOUR A1 - Guerrero-Ramirez, Nathaly Rokssana A1 - Craven, Dylan A1 - Reich, Peter B. A1 - Ewel, John J. A1 - Isbell, Forest A1 - Koricheva, Julia A1 - Parrotta, John A. A1 - Auge, Harald A1 - Erickson, Heather E. A1 - Forrester, David I. A1 - Hector, Andy A1 - Joshi, Jasmin Radha A1 - Montagnini, Florencia A1 - Palmborg, Cecilia A1 - Piotto, Daniel A1 - Potvin, Catherine A1 - Roscher, Christiane A1 - van Ruijven, Jasper A1 - Tilman, David A1 - Wilsey, Brian A1 - Eisenhauer, Nico T1 - Diversity-dependent temporal divergence of ecosystem functioning in experimental ecosystems JF - Nature ecology & evolution N2 - The effects of biodiversity on ecosystem functioning generally increase over time, but the underlying processes remain unclear. Using 26 long-term grassland and forest experimental ecosystems, we demonstrate that biodiversity-ecosystem functioning relationships strengthen mainly by greater increases in functioning in high-diversity communities in grasslands and forests. In grasslands, biodiversity effects also strengthen due to decreases in functioning in low-diversity communities. Contrasting trends across grasslands are associated with differences in soil characteristics. Y1 - 2017 U6 - https://doi.org/10.1038/s41559-017-0325-1 SN - 2397-334X VL - 1 IS - 11 SP - 1639 EP - 1642 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Braunger, Steffen A1 - Mundt, Laura E. A1 - Wolff, Christian Michael A1 - Mews, Mathias A1 - Rehermann, Carolin A1 - Jost, Marko A1 - Tejada, Alvaro A1 - Eisenhauer, David A1 - Becker, Christiane A1 - Andres Guerra, Jorge A1 - Unger, Eva A1 - Korte, Lars A1 - Neher, Dieter A1 - Schubert, Martin C. A1 - Rech, Bernd A1 - Albrecht, Steve T1 - Cs(x)FA(1-x)Pb(l(1-y)Br(y))(3) Perovskite Compositions BT - the Appearance of Wrinkled Morphology and its Impact on Solar Cell Performance JF - The journal of physical chemistry : C, Nanomaterials and interfaces N2 - We report on the formation of wrinkle-patterned surface morphologies in cesium formamidinium-based Cs(x)FA(1-y)Pb(I1-yBry)(3) perovskite compositions with x = 0-0.3 and y = 0-0.3 under various spin-coating conditions. By varying the Cs and Br contents, the perovskite precursor solution concentration and the spin-coating procedure, the occurrence and characteristics of the wrinkle-shaped morphology can be tailored systematically. Cs(0.17)FA(0.83)Pb(I0.83Br0.17)(3) perovskite layers were analyzed regarding their surface roughness, microscopic structure, local and overall composition, and optoelectronic properties. Application of these films in p-i-n perovskite solar cells (PSCs) with indium-doped tin oxide/NiOx/perovskite/C-60/bathocuproine/Cu architecture resulted in up to 15.3 and 17.0% power conversion efficiency for the flat and wrinkled morphology, respectively. Interestingly, we find slightly red-shifted photoluminescence (PL) peaks for wrinkled areas and we are able to directly correlate surface topography with PL peak mapping. This is attributed to differences in the local grain size, whereas there is no indication for compositional demixing in the films. We show that the perovskite composition, crystallization kinetics, and layer thickness strongly influence the formation of wrinkles which is proposed to be related to the release of compressive strain during perovskite crystallization. Our work helps us to better understand film formation and to further improve the efficiency of PSCs with widely used mixed-perovskite compositions. Y1 - 2018 U6 - https://doi.org/10.1021/acs.jpcc.8b06459 SN - 1932-7447 SN - 1932-7455 VL - 122 IS - 30 SP - 17123 EP - 17135 PB - American Chemical Society CY - Washington ER -