41 citations · 59 across the 6 of their papers we have counts for
7 papers
How Charge Carrier Exchange between Absorber and Contact influences Time Constants in the Frequency Domain Response of Perovskite Solar Cells
Sandheep Ravishankar, Zhifa Liu, Yueming Wang +2
A model is derived for the frequency- and time-domain opto-electronic response of perovskite solar cells (PSCs) that emphasizes the role of charge carrier exchange, .i.e. extractio…
Quantifying Charge Extraction and Recombination Using the Rise and Decay of the Transient Photovoltage of Perovskite Solar Cells
Lisa Krückemeier, Zhifa Liu, Thomas Kirchartz +1
The extraction of photogenerated charge carriers and the generation of a photovoltage belong to the fundamental functionalities of any solar cell. These processes happen not instan…
Fill Factor Losses and Deviations from the Superposition Principle in Lead-Halide Perovskite Solar Cells
David Grabowski, Zhifa Liu, Gunnar Schöpe +2
The enhancement of the fill factor in the current generation of perovskite solar cells is the key for further efficiency improvement. Thus, methods to quantify the fill factor loss…
Multilayer Capacitances: How Selective Contacts Affect Capacitance Measurements of Perovskite Solar Cells
Sandheep Ravishankar, Zhifa Liu, Uwe Rau +1
Capacitance measurements as a function of voltage, frequency and temperature are useful tools to identify fundamental parameters that affect solar cell operation. Techniques such a…
Understanding Transient Photoluminescence in Halide Perovskite Layer Stacks and Solar Cells
Lisa Krückemeier, Benedikt Krogmeier, Zhifa Liu +2
While transient photoluminescence measurements are a very popular tool to monitor the charge-carrier dynamics in the field of halide perovskite photovoltaics, interpretation of dat…
Interface Optimization via Fullerene Blends Enables Open-Circuit Voltages of 1.35 V in CH3NH3Pb(I0.8Br0.2)3 Solar Cells
Zhifa Liu, Johanna Siekmann, Benjamin Klingebiel +2
Non-radiative recombination processes are the biggest hindrance to approaching the radiative limit of the open-circuit voltage for wide-band gap perovskite solar cells. In addition…
Defect tolerant device geometries
Basita Das, Zhifa Liu, Irene Aguilera +2
The term defect tolerance is widely used in literature to describe materials such as lead-halides which exhibit long non-radiative lifetimes of carriers despite possessing a large…