TY - GEN A1 - Francke, Till A1 - Heistermann, Maik A1 - Köhli, Markus A1 - Budach, Christian A1 - Schrön, Martin A1 - Oswald, Sascha T1 - Assessing the feasibility of a directional cosmic-ray neutron sensing sensor for estimating soil moisture T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Cosmic-ray neutron sensing (CRNS) is a non-invasive tool for measuring hydrogen pools such as soil moisture, snow or vegetation. The intrinsic integration over a radial hectare-scale footprint is a clear advantage for averaging out small-scale heterogeneity, but on the other hand the data may become hard to interpret in complex terrain with patchy land use. This study presents a directional shielding approach to prevent neutrons from certain angles from being counted while counting neutrons entering the detector from other angles and explores its potential to gain a sharper horizontal view on the surrounding soil moisture distribution. Using the Monte Carlo code URANOS (Ultra Rapid Neutron-Only Simulation), we modelled the effect of additional polyethylene shields on the horizontal field of view and assessed its impact on the epithermal count rate, propagated uncertainties and aggregation time. The results demonstrate that directional CRNS measurements are strongly dominated by isotropic neutron transport, which dilutes the signal of the targeted direction especially from the far field. For typical count rates of customary CRNS stations, directional shielding of half-spaces could not lead to acceptable precision at a daily time resolution. However, the mere statistical distinction of two rates should be feasible. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1228 KW - water-balance KW - quantification KW - calibration KW - validation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-544229 SN - 1866-8372 SP - 75 EP - 92 ER - TY - GEN A1 - Kühn, Danilo A1 - Sorgenfrei, Nomi A1 - Giangrisostomi, Erika A1 - Jay, Raphael Martin A1 - Musazayb, Abdurrahman A1 - Ovsyannikov, Ruslan A1 - Stråhlman, Christian A1 - Svensson, Svante A1 - Mårtensson, Nils A1 - Föhlisch, Alexander T1 - Capabilities of angle resolved time of flight electron spectroscopy with the 60 degrees wide angle acceptance lens T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - The simultaneous detection of energy, momentum and temporal information in electron spectroscopy is the key aspect to enhance the detection efficiency in order to broaden the range of scientific applications. Employing a novel 60 degrees wide angle acceptance lens system, based on an additional accelerating electron optical element, leads to a significant enhancement in transmission over the previously employed 30 degrees electron lenses. Due to the performance gain, optimized capabilities for time resolved electron spectroscopy and other high transmission applications with pulsed ionizing radiation have been obtained. The energy resolution and transmission have been determined experimentally utilizing BESSY II as a photon source. Four different and complementary lens modes have been characterized. (C) 2017 The Authors. Published by Elsevier B.V. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 782 KW - Artof KW - electron spectroscopy KW - wide angle KW - time of flight KW - energy resolution KW - synchrotron Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-436629 SN - 1866-8372 IS - 782 SP - 45 EP - 50 ER - TY - GEN A1 - Boldt, Julia A1 - Leber, Alexander W. A1 - Bonaventura, Klaus A1 - Sohns, Christian A1 - Stula, Martin A1 - Huppertz, Alexander A1 - Haverkamp, Wilhelm A1 - Dorenkamp, Marc T1 - Cost-effectiveness of cardiovascular magnetic resonance and single-photon emission computed tomography for diagnosis of coronary artery disease in Germany T2 - Postprints der Universität Potsdam Humanwissenschaftliche Reihe N2 - Background: Recent studies have demonstrated a superior diagnostic accuracy of cardiovascular magnetic resonance (CMR) for the detection of coronary artery disease (CAD). We aimed to determine the comparative cost-effectiveness of CMR versus single-photon emission computed tomography (SPECT). Methods: Based on Bayes' theorem, a mathematical model was developed to compare the cost-effectiveness and utility of CMR with SPECT in patients with suspected CAD. Invasive coronary angiography served as the standard of reference. Effectiveness was defined as the accurate detection of CAD, and utility as the number of quality-adjusted life-years (QALYs) gained. Model input parameters were derived from the literature, and the cost analysis was conducted from a German health care payer's perspective. Extensive sensitivity analyses were performed. Results: Reimbursement fees represented only a minor fraction of the total costs incurred by a diagnostic strategy. Increases in the prevalence of CAD were generally associated with improved cost-effectiveness and decreased costs per utility unit (Delta QALY). By comparison, CMR was consistently more cost-effective than SPECT, and showed lower costs per QALY gained. Given a CAD prevalence of 0.50, CMR was associated with total costs of (sic)6,120 for one patient correctly diagnosed as having CAD and with (sic)2,246 per Delta QALY gained versus (sic)7,065 and (sic)2,931 for SPECT, respectively. Above a threshold value of CAD prevalence of 0.60, proceeding directly to invasive angiography was the most cost-effective approach. Conclusions: In patients with low to intermediate CAD probabilities, CMR is more cost-effective than SPECT. Moreover, lower costs per utility unit indicate a superior clinical utility of CMR. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 551 KW - cost-effectiveness KW - cardiovascular magnetic resonance KW - scintigraphy KW - coronary angiography KW - coronary artery disease Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-430107 SN - 1866-8364 IS - 551 ER - TY - GEN A1 - Stolterfoht, Martin A1 - Grischek, Max A1 - Caprioglio, Pietro A1 - Wolff, Christian Michael A1 - Gutierrez-Partida, Emilio A1 - Peña-Camargo, Francisco A1 - Rothhardt, Daniel A1 - Zhang, Shanshan A1 - Raoufi, Meysam A1 - Wolansky, Jakob A1 - Abdi-Jalebi, Mojtaba A1 - Stranks, Samuel D. A1 - Albrecht, Steve A1 - Kirchartz, Thomas A1 - Neher, Dieter T1 - How to quantify the efficiency potential of neat perovskite films BT - Perovskite semiconductors with an implied efficiency exceeding 28% T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Perovskite photovoltaic (PV) cells have demonstrated power conversion efficiencies (PCE) that are close to those of monocrystalline silicon cells; however, in contrast to silicon PV, perovskites are not limited by Auger recombination under 1-sun illumination. Nevertheless, compared to GaAs and monocrystalline silicon PV, perovskite cells have significantly lower fill factors due to a combination of resistive and non-radiative recombination losses. This necessitates a deeper understanding of the underlying loss mechanisms and in particular the ideality factor of the cell. By measuring the intensity dependence of the external open-circuit voltage and the internal quasi-Fermi level splitting (QFLS), the transport resistance-free efficiency of the complete cell as well as the efficiency potential of any neat perovskite film with or without attached transport layers are quantified. Moreover, intensity-dependent QFLS measurements on different perovskite compositions allows for disentangling of the impact of the interfaces and the perovskite surface on the non-radiative fill factor and open-circuit voltage loss. It is found that potassium-passivated triple cation perovskite films stand out by their exceptionally high implied PCEs > 28%, which could be achieved with ideal transport layers. Finally, strategies are presented to reduce both the ideality factor and transport losses to push the efficiency to the thermodynamic limit. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1434 KW - non-radiative interface recombination KW - perovskite solar cells KW - photoluminescence Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-516622 SN - 1866-8372 IS - 17 ER - TY - GEN A1 - Wang, Qiong A1 - Smith, Joel A. A1 - Skroblin, Dieter A1 - Steele, Julian A. A1 - Wolff, Christian Michael A1 - Caprioglio, Pietro A1 - Stolterfoht, Martin A1 - Köbler, Hans A1 - Turren-Cruz, Silver-Hamill A1 - Li, Meng A1 - Gollwitzer, Christian A1 - Neher, Dieter A1 - Abate, Antonio T1 - Managing phase purities and crystal orientation for high-performance and photostable cesium lead halide perovskite solar cells T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Inorganic perovskites with cesium (Cs+) as the cation have great potential as photovoltaic materials if their phase purity and stability can be addressed. Herein, a series of inorganic perovskites is studied, and it is found that the power conversion efficiency of solar cells with compositions CsPbI1.8Br1.2, CsPbI2.0Br1.0, and CsPbI2.2Br0.8 exhibits a high dependence on the initial annealing step that is found to significantly affect the crystallization and texture behavior of the final perovskite film. At its optimized annealing temperature, CsPbI1.8Br1.2 exhibits a pure orthorhombic phase and only one crystal orientation of the (110) plane. Consequently, this allows for the best efficiency of up to 14.6% and the longest operational lifetime, T-S80, of approximate to 300 h, averaged of over six solar cells, during the maximum power point tracking measurement under continuous light illumination and nitrogen atmosphere. This work provides essential progress on the enhancement of photovoltaic performance and stability of CsPbI3 - xBrx perovskite solar cells. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1210 KW - cesium lead halides KW - crystal orientation KW - inorganic perovskites KW - ISOS-L-1I protocol KW - phase purity KW - photostability Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-525374 SN - 1866-8372 IS - 9 ER - TY - GEN A1 - Kaboth-Bahr, Stefanie A1 - Bahr, André A1 - Stepanek, Christian A1 - Catunda, Maria Carolina Amorim A1 - Karas, Cyrus A1 - Ziegler, Martin A1 - García-Gallardo, Ángela A1 - Grunert, Patrick T1 - Mediterranean heat injection to the North Atlantic delayed the intensification of Northern Hemisphere glaciations T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The intensification of Northern Hemisphere glaciations at the end of the Pliocene epoch marks one of the most substantial climatic shifts of the Cenozoic. Despite global cooling, sea surface temperatures in the high latitude North Atlantic Ocean rose between 2.9–2.7 million years ago. Here we present sedimentary geochemical proxy data from the Gulf of Cadiz to reconstruct the variability of Mediterranean Outflow Water, an important heat source to the North Atlantic. We find evidence for enhanced production of Mediterranean Outflow from the mid-Pliocene to the late Pliocene which we infer could have driven a sub-surface heat channel into the high-latitude North Atlantic. We then use Earth System Models to constrain the impact of enhanced Mediterranean Outflow production on the northward heat transport in the North Atlantic. In accord with the proxy data, the numerical model results support the formation of a sub-surface channel that pumped heat from the subtropics into the high latitude North Atlantic. We further suggest that this mechanism could have delayed ice sheet growth at the end of the Pliocene. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1237 Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-548762 SN - 1866-8372 IS - 1237 SP - 1 EP - 9 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - GEN A1 - Gorski, Mathias A1 - Jung, Bettina A1 - Li, Yong A1 - Matias-Garcia, Pamela R. A1 - Wuttke, Matthias A1 - Coassin, Stefan A1 - Thio, Chris H. L. A1 - Kleber, Marcus E. A1 - Winkler, Thomas W. A1 - Wanner, Veronika A1 - Chai, Jin-Fang A1 - Chu, Audrey Y. A1 - Cocca, Massimiliano A1 - Feitosa, Mary F. A1 - Ghasemi, Sahar A1 - Hoppmann, Anselm A1 - Horn, Katrin A1 - Li, Man A1 - Nutile, Teresa A1 - Scholz, Markus A1 - Sieber, Karsten B. A1 - Teumer, Alexander A1 - Tin, Adrienne A1 - Wang, Judy A1 - Tayo, Bamidele O. A1 - Ahluwalia, Tarunveer S. A1 - Almgren, Peter A1 - Bakker, Stephan J. L. A1 - Banas, Bernhard A1 - Bansal, Nisha A1 - Biggs, Mary L. A1 - Boerwinkle, Eric A1 - Böttinger, Erwin A1 - Brenner, Hermann A1 - Carroll, Robert J. A1 - Chalmers, John A1 - Chee, Miao-Li A1 - Chee, Miao-Ling A1 - Cheng, Ching-Yu A1 - Coresh, Josef A1 - de Borst, Martin H. A1 - Degenhardt, Frauke A1 - Eckardt, Kai-Uwe A1 - Endlich, Karlhans A1 - Franke, Andre A1 - Freitag-Wolf, Sandra A1 - Gampawar, Piyush A1 - Gansevoort, Ron T. A1 - Ghanbari, Mohsen A1 - Gieger, Christian A1 - Hamet, Pavel A1 - Ho, Kevin A1 - Hofer, Edith A1 - Holleczek, Bernd A1 - Foo, Valencia Hui Xian A1 - Hutri-Kahonen, Nina A1 - Hwang, Shih-Jen A1 - Ikram, M. Arfan A1 - Josyula, Navya Shilpa A1 - Kahonen, Mika A1 - Khor, Chiea-Chuen A1 - Koenig, Wolfgang A1 - Kramer, Holly A1 - Kraemer, Bernhard K. A1 - Kuehnel, Brigitte A1 - Lange, Leslie A. A1 - Lehtimaki, Terho A1 - Lieb, Wolfgang A1 - Loos, Ruth J. F. A1 - Lukas, Mary Ann A1 - Lyytikainen, Leo-Pekka A1 - Meisinger, Christa A1 - Meitinger, Thomas A1 - Melander, Olle A1 - Milaneschi, Yuri A1 - Mishra, Pashupati P. A1 - Mononen, Nina A1 - Mychaleckyj, Josyf C. A1 - Nadkarni, Girish N. A1 - Nauck, Matthias A1 - Nikus, Kjell A1 - Ning, Boting A1 - Nolte, Ilja M. A1 - O'Donoghue, Michelle L. A1 - Orho-Melander, Marju A1 - Pendergrass, Sarah A. A1 - Penninx, Brenda W. J. H. A1 - Preuss, Michael H. A1 - Psaty, Bruce M. A1 - Raffield, Laura M. A1 - Raitakari, Olli T. A1 - Rettig, Rainer A1 - Rheinberger, Myriam A1 - Rice, Kenneth M. A1 - Rosenkranz, Alexander R. A1 - Rossing, Peter A1 - Rotter, Jerome A1 - Sabanayagam, Charumathi A1 - Schmidt, Helena A1 - Schmidt, Reinhold A1 - Schoettker, Ben A1 - Schulz, Christina-Alexandra A1 - Sedaghat, Sanaz A1 - Shaffer, Christian M. A1 - Strauch, Konstantin A1 - Szymczak, Silke A1 - Taylor, Kent D. A1 - Tremblay, Johanne A1 - Chaker, Layal A1 - van der Harst, Pim A1 - van der Most, Peter J. A1 - Verweij, Niek A1 - Voelker, Uwe A1 - Waldenberger, Melanie A1 - Wallentin, Lars A1 - Waterworth, Dawn M. A1 - White, Harvey D. A1 - Wilson, James G. A1 - Wong, Tien-Yin A1 - Woodward, Mark A1 - Yang, Qiong A1 - Yasuda, Masayuki A1 - Yerges-Armstrong, Laura M. A1 - Zhang, Yan A1 - Snieder, Harold A1 - Wanner, Christoph A1 - Boger, Carsten A. A1 - Kottgen, Anna A1 - Kronenberg, Florian A1 - Pattaro, Cristian A1 - Heid, Iris M. T1 - Meta-analysis uncovers genome-wide significant variants for rapid kidney function decline T2 - Zweitveröffentlichungen der Universität Potsdam : Reihe der Digital Engineering Fakultät N2 - Rapid decline of glomerular filtration rate estimated from creatinine (eGFRcrea) is associated with severe clinical endpoints. In contrast to cross-sectionally assessed eGFRcrea, the genetic basis for rapid eGFRcrea decline is largely unknown. To help define this, we meta-analyzed 42 genome-wide association studies from the Chronic Kidney Diseases Genetics Consortium and United Kingdom Biobank to identify genetic loci for rapid eGFRcrea decline. Two definitions of eGFRcrea decline were used: 3 mL/min/1.73m(2)/year or more ("Rapid3"; encompassing 34,874 cases, 107,090 controls) and eGFRcrea decline 25% or more and eGFRcrea under 60 mL/min/1.73m(2) at follow-up among those with eGFRcrea 60 mL/min/1.73m(2) or more at baseline ("CKDi25"; encompassing 19,901 cases, 175,244 controls). Seven independent variants were identified across six loci for Rapid3 and/or CKDi25: consisting of five variants at four loci with genome-wide significance (near UMOD-PDILT (2), PRKAG2, WDR72, OR2S2) and two variants among 265 known eGFRcrea variants (near GATM, LARP4B). All these loci were novel for Rapid3 and/or CKDi25 and our bioinformatic follow-up prioritized variants and genes underneath these loci. The OR2S2 locus is novel for any eGFRcrea trait including interesting candidates. For the five genome-wide significant lead variants, we found supporting effects for annual change in blood urea nitrogen or cystatin-based eGFR, but not for GATM or (LARP4B). Individuals at high compared to those at low genetic risk (8-14 vs. 0-5 adverse alleles) had a 1.20-fold increased risk of acute kidney injury (95% confidence interval 1.08-1.33). Thus, our identified loci for rapid kidney function decline may help prioritize therapeutic targets and identify mechanisms and individuals at risk for sustained deterioration of kidney function. T3 - Zweitveröffentlichungen der Universität Potsdam : Reihe der Digital Engineering Fakultät - 19 KW - acute kidney injury KW - end-stage kidney disease KW - genome-wide association KW - study KW - rapid eGFRcrea decline Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-565379 IS - 19 ER - TY - GEN A1 - Hocher, Berthold A1 - Oberthür, Dominik A1 - Slowinski, Torsten A1 - Querfeld, Uwe A1 - Schaefer, Franz A1 - Doyon, Anke A1 - Tepel, Martin A1 - Roth, Heinz J. A1 - Grön, Hans J. A1 - Reichetzeder, Christoph A1 - Betzel, Christian A1 - Armbruster, Franz Paul T1 - Modeling of oxidized PTH (oxPTH) and non-oxidized PTH (n-oxPTH) receptor binding and relationship of oxidized to non-oxidized PTH in children with chronic renal failure, adult patients on hemodialysis and kidney transplant recipients N2 - Background: The biological properties of oxidized and non-oxidized PTH are substantially different. Oxidized PTH (oxPTH) loses its PTH receptor-stimulating properties, whereas non-oxidized PTH (n-oxPTH) is a full agonist of the receptor. This was described in more than 20 well published studies in the 1970(s) and 80(s). However, PTH oxidation has been ignored during the development of PTH assays for clinical use so far. Even the nowadays used third generation assay systems do not consider oxidation of PTH. We recently developed an assay to differentiate between oxPTH and n-oxPTH. In the current study we established normal values for this assay system. Furthermore, we compare the ratio of oxPTH to n-oxPTH in different population with chronic renal failure: 620 children with renal failure stage 2-4 of the 4C study, 342 adult patients on dialysis, and 602 kidney transplant recipients. In addition, we performed modeling of the interaction of either oxPTH or n-oxPTH with the PTH receptor using biophysical structure approaches. Results: The children had the highest mean as well as maximum n-oxPTH concentrations as compared to adult patients (both patients on dialysis as well as kidney transplant recipients). The relationship between oxPTH and n-oxPTH of individual patients varied substantially in all three populations with renal impairment. The analysis of n-oxPTH in 89 healthy control subjects revealed that n-oxPTH concentrations in patient with renal failure were higher as compared to healthy adult controls (2.25-fold in children with renal failure, 1.53-fold in adult patients on dialysis, and 1.56-fold in kidney transplant recipients, respectively). Computer assisted biophysical structure modeling demonstrated, however, minor sterical- and/or electrostatic changes in oxPTH and n-oxPTH. This indicated that PTH oxidation may induce refolding of PTH and hence alters PTH-PTH receptor interaction via oxidation induced three-dimensional structure alteration of PTH. Conclusion: A huge proportion of circulating PTH measured by current state-of-the-art assay systems is oxidized and thus not biologically active. The relationship between oxPTH and n-oxPTH of individual patients varied substantially. Non-oxidized PTH concentrations are 1.5 - 2.25 fold higher in patients with renal failure as compared to health controls. Measurements of n-oxPTH may reflect the hormone status more precise. The iPTH measures describes most likely oxidative stress in patients with renal failure rather than the PTH hormone status. This, however, needs to be demonstrated in further clinical studies. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 343 KW - n-oxPTH KW - chronic renal failure KW - kidney transplantation KW - hemodialysis KW - oxidation KW - PTH KW - chronic renal failure in children Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-399980 ER - TY - GEN A1 - Wolff, Christian Michael A1 - Caprioglio, Pietro A1 - Stolterfoht, Martin A1 - Neher, Dieter T1 - Nonradiative recombination in perovskite solar cells BT - the role of interfaces T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Perovskite solar cells combine high carrier mobilities with long carrier lifetimes and high radiative efficiencies. Despite this, full devices suffer from significant nonradiative recombination losses, limiting their VOC to values well below the Shockley–Queisser limit. Here, recent advances in understanding nonradiative recombination in perovskite solar cells from picoseconds to steady state are presented, with an emphasis on the interfaces between the perovskite absorber and the charge transport layers. Quantification of the quasi‐Fermi level splitting in perovskite films with and without attached transport layers allows to identify the origin of nonradiative recombination, and to explain the VOC of operational devices. These measurements prove that in state‐of‐the‐art solar cells, nonradiative recombination at the interfaces between the perovskite and the transport layers is more important than processes in the bulk or at grain boundaries. Optical pump‐probe techniques give complementary access to the interfacial recombination pathways and provide quantitative information on transfer rates and recombination velocities. Promising optimization strategies are also highlighted, in particular in view of the role of energy level alignment and the importance of surface passivation. Recent record perovskite solar cells with low nonradiative losses are presented where interfacial recombination is effectively overcome—paving the way to the thermodynamic efficiency limit. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 772 KW - interfacial recombination KW - open‐circuit voltage KW - perovskite solar cells KW - photoluminescence Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-437626 SN - 1866-8372 IS - 772 ER - TY - GEN A1 - Caprioglio, Pietro A1 - Stolterfoht, Martin A1 - Wolff, Christian Michael A1 - Unold, Thomas A1 - Rech, Bernd A1 - Albrecht, Steve A1 - Neher, Dieter T1 - On the relation between the open‐circuit voltage and quasi‐Fermi level splitting in efficient perovskite solar cells T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Today's perovskite solar cells (PSCs) are limited mainly by their open‐circuit voltage (VOC) due to nonradiative recombination. Therefore, a comprehensive understanding of the relevant recombination pathways is needed. Here, intensity‐dependent measurements of the quasi‐Fermi level splitting (QFLS) and of the VOC on the very same devices, including pin‐type PSCs with efficiencies above 20%, are performed. It is found that the QFLS in the perovskite lies significantly below its radiative limit for all intensities but also that the VOC is generally lower than the QFLS, violating one main assumption of the Shockley‐Queisser theory. This has far‐reaching implications for the applicability of some well‐established techniques, which use the VOC as a measure of the carrier densities in the absorber. By performing drift‐diffusion simulations, the intensity dependence of the QFLS, the QFLS‐VOC offset and the ideality factor are consistently explained by trap‐assisted recombination and energetic misalignment at the interfaces. Additionally, it is found that the saturation of the VOC at high intensities is caused by insufficient contact selectivity while heating effects are of minor importance. It is concluded that the analysis of the VOC does not provide reliable conclusions of the recombination pathways and that the knowledge of the QFLS‐VOC relation is of great importance. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 774 KW - electro‐optical materials KW - perovskite solar cells KW - photovoltaic devices KW - thin films Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-437595 SN - 1866-8372 IS - 774 ER -