Publications by Leo-Philipp Heiniger

Strong Photocurrent Amplification in Perovskite Solar Cells with a Porous TiO2 Blocking Layer under Reverse Bias

Michael Graetzel, Mohammad Khaja Nazeeruddin, Shaik Mohammed Zakeeruddin, Mohammad Ibrahim Dar, Thomas Moehl, Yonghui Lee, Fabrizio Giordano, Konrad Domanski, Leo-Philipp Heiniger, Jeong-Hyeok Im

We investigate two different types of TiO2 blocking layer (BL) deposition techniques commonly used in solid-state methylammonium lead triiodide perovskite (MaPbI(3))-based solar cells. Although these BLs lead to similar photovoltaic device performance, the ...

Amer Chemical Soc2014

New Approaches for Improved Photon Management in Dye-Sensitized Solar Cells

Leo-Philipp Heiniger

EPFL2014

Mesoporous TiO2 Beads Offer Improved Mass Transport for Cobalt-Based Redox Couples Leading to High Efficiency Dye-Sensitized Solar Cells

Michael Graetzel, Thomas Moehl, Fabrizio Giordano, Leo-Philipp Heiniger

Overcoming ionic diffusion limitations is essential for the development of high-efficiency dye-sensitized solar cells based on cobalt redox mediators. Here, improved mass transport is reported for photoanodes composed of mesoporous TiO2 beads of varying po ...

Wiley-VCH Verlag Berlin2014

Nanocrystalline Rutile Electron Extraction Layer Enables Low-Temperature Solution Processed Perovskite Photovoltaics with 13.7% Efficiency

Michael Graetzel, Mohammad Khaja Nazeeruddin, Aswani Yella, Peng Gao, Leo-Philipp Heiniger

We demonstrate low-temperature (70 degrees C) solution processing of TiO2/CH3NH3PbI3 based solar cells, resulting in impressive power conversion efficiency (PCE) of 13.7%. Along with the high efficiency, a strikingly high open circuit potential (V-OC) of 1 ...

American Chemical Society2014

Diffusion and adsorption of dye molecules in mesoporous TiO2 photoelectrodes studied by indirect nanoplasmonic sensing

Michael Graetzel, Leo-Philipp Heiniger, Bengt Kasemo

In this study, we used Hidden Interface-Indirect Nanoplasmonic Sensing (HI-INPS) for real time monitoring of dye impregnation (adsorption-diffusion process) of mesoporous TiO2 electrodes of the kind used in dye-sensitized solar cells. We measured the dye p ...

Royal Society of Chemistry2013

See-Through Dye-Sensitized Solar Cells: Photonic Reflectors for Tandem and Building Integrated Photovoltaics

Michael Graetzel, Nicolas Tétreault, Leo-Philipp Heiniger, Yang Yang

See-through dye-sensitized solar cells with 1D photonic crystal Bragg reflector photoanodes show an increase in peak external quantum efficiency of 47% while still maintaining high fill factors, resulting in an almost 40% increase in power conversion effic ...

Wiley-Blackwell2013

Low temperature crystalline titanium dioxide by atomic layer deposition for dye-sensitized solar cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Pascal Comte, Aswani Yella, Morgan Mertens Stefik, Aravind Kumar Chandiran, Leo-Philipp Heiniger

Low temperature processing of dye-sensitized solar cells (DSC) is crucial to enable commercialization with low-cost, plastic substrates. Prior studies have focused on mechanical compression of premade particles on plastic or glass substrates, however, this ...

Amer Chemical Soc2013

Time-Resolved Indirect Nanoplasmonic Sensing Spectroscopy of Dye Molecule Interactions with Dense and Mesoporous TiO2 Films

Michael Graetzel, Leo-Philipp Heiniger, Bengt Kasemo

Indirect nanoplasmonic sensing (INPS) is an experimental platform exploiting localized surface plasmon resonance (LSPR) detection of processes in nanomaterials, molecular assemblies, and films at the nanoscale. Here we have for the first time applied INPS ...

American Chemical Society2012

High-Efficiency Dye-Sensitized Solar Cell with Three-Dimensional Photoanode

Michael Graetzel, Shaik Mohammed Zakeeruddin, Nicolas Tétreault, Thomas Moehl, Jérémie Minh-Châu Brillet, Leo-Philipp Heiniger

Herein, we present a straightforward bottom-up synthesis of a high electron mobility and highly light scattering macroporous photoanode for dye-sensitized solar cells. The dense three-dimensional Al/ZnO, SnO2, or TiO2 host integrates a conformal passivatio ...

American Chemical Society2011

Dye-Sensitized Solar Cells Employing a Single Film of Mesoporous TiO2 Beads Achieve Power Conversion Efficiencies Over 10%

Michael Graetzel, Pascal Comte, Leo-Philipp Heiniger

Dye-sensitized solar cells employing mesoporous TiO2 beads have demonstrated longer electron diffusion lengths and extended electron lifetimes over Degussa P25 titania electrodes due to the well interconnected, densely packed nanocrystalline TiO2 particles ...

American Chemical Society2010