Ulf Anders Hagfeldt

Cette personne n’est plus à l’EPFL

Publications associées (575)

SnS Quantum Dots as Hole Transporter of Perovskite Solar Cells

Shaik Mohammed Zakeeruddin, Yuhang Liu, Ulf Anders Hagfeldt, Peng Wang, Yang Li, Dan Ren, Zaiwei Wang, Xiaofei Dong

Perovskite solar cells have achieved comparable power conversion efficiencies as commercial silicon cells, making the issue of long-term operation stability as the most critical scientific factor toward industrial realization. In this work, we introduce Sn ...

AMER CHEMICAL SOC2019

Conversion of carbon dioxide into hydrocarbons using solar energy is an attractive strategy for storing such a renewable source of energy into the form of chemical energy (a fuel). This can be achieved in a system coupling a photovoltaic (PV) cell to an el ...

PNAS2019

Conjugated pi-spacers are used to improve the light harvesting properties of sensitizers for dye-sensitized solar cells. In several recent works, furan has outperformed other popular pi-spacers such as thiophene and phenyl. One of the best performing pheno ...

ROYAL SOC CHEMISTRY2019

A comprehensive experimental study of five fundamental phenothiazine geometries increasing the diversity of the phenothiazine dye class for dye-sensitized solar cells

Ulf Anders Hagfeldt

Phenothiazine is a versatile scaffold frequently used in both pharmaceutical and photovoltaic applications. Still, the structural diversity within the class of phenothiazine sensitizers for dye-sensitized solar cells is minute. Substituents are found in 3, ...

ELSEVIER SCI LTD2019

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The stability of perovskite solar cells is a key issue for industrial development. One reason for this is the volatile organic methylammonium (MA) cation, which is prone to degas under elevated temperatures from the perovskite. At the same time, small amou ...

2019

Nanoscale mapping of chemical composition in organic-inorganic hybrid perovskite films

Ulf Anders Hagfeldt, Silver Hamill Turren Cruz, Rodrigo Szostak

Lead-based organic-inorganic hybrid perovskite (OIHP) solar cells can attain efficiencies over 20%. However, the impact of ion mobility and/or organic depletion, structural changes, and segregation under operating conditions urge for decisive and more accu ...

American Association for the Advancement of Science (AAAS)2019

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Three-dimensional (3D) perovskite materials display remarkable potential in photovoltaics owing to their superior solar-to-electric power conversion efficiency, with current efforts focused on improving stability. Two-dimensional (2D) perovskite analogues ...

AMER CHEMICAL SOC2019

The electron-injection energy losses of dye-sensitized solar cells (DSSCs) are among the fundamental problems hindering their successful breakthrough application. Two triazatruxene (TAT)-based sensitizers, with one containing a flexible Z-type double bond ...

AMER CHEMICAL SOC2019

Blocking the Charge Recombination with Diiodide Radicals by TiO2 Compact Layer in Dye-Sensitized Solar Cells

Nikolaos Vlachopoulos, Ulf Anders Hagfeldt, Kazuteru Nonomura

The addition of a compact titanium dioxide (TiO2) layer between the fluorine-doped tin oxide (FTO) coated glass substrate and the mesoporous TiO2 layer in the dye-sensitized solar cell (DSC) based on the iodide/triiodide redox couple (I-/I-3(-)) is known t ...

ELECTROCHEMICAL SOC INC2019

Photoinduced Lattice Symmetry Enhancement in Mixed Hybrid Perovskites and Its Beneficial Effect on the Recombination Behavior

Ulf Anders Hagfeldt, Hui-Seon Kim

The strategy of mixing cations and halides in hybrid organic lead halide perovskites has recently been shown to be very successful in achieving high efficiency with long-term perovskite solar cell stability. In this study, the effect of photoexcitation on ...

WILEY-V C H VERLAG GMBH2019