Publications by Thomas Paul Baumeler

High-Performance Perovskite Solar Cells with Zwitterion-Capped-ZnO Quantum Dots as Electron Transport Layer and NH4X (X = F, Cl, Br) Assisted Interfacial Engineering

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Thomas Paul Baumeler, Essa Awadh R Alharbi, Rashmi Runjhun, Felix Thomas Eickemeyer, Viktor Skorjanc, Anurag Krishna, Georgios Kakavelakis

The systematic advances in the power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs) have been driven by the developments of perovskite materials, electron transport layer (ETL) materials, and interfacial passivation between the ...

Wiley2024

Surface Passivation of FAPbI3-Rich Perovskite with Cesium Iodide Outperforms Bulk Incorporation

Michael Graetzel, Jacques-Edouard Moser, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Jun Ho Yum, Kevin Sivula, Thomas Paul Baumeler, Essa Awadh R Alharbi, Brian Irving Carlsen, Jing Gao, George Cameron Fish, Felix Thomas Eickemeyer, Lukas Pfeifer, Georgios Kakavelakis

Metal halide perovskites (MHPs) have shown an incredible increase in efficiency, reaching as high as 25.7%, which now competes with traditional photovoltaic technologies. Herein, we excluded CsX and RbX (X = I–, Br–, Cl–), the most commonly used cations to ...

2023

Cooperative passivation of perovskite solar cells by alkyldimethylammonium halide amphiphiles

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Thomas Paul Baumeler, David Lyndon Emsley, Essa Awadh R Alharbi, Mathias Dankl, Aditya Mishra, Felix Thomas Eickemeyer, Michael Allan Hope, Anurag Krishna, Olivier Ouellette, Lukas Pfeifer, Nikolaos Lempesis, Georgios Kakavelakis

2023

Champion Device Architectures for Low-Cost and Stable Single-Junction Perovskite Solar Cells

Michael Graetzel, Thomas Paul Baumeler, Mohammad Ibrahim Dar, Neha Arora

High power conversion efficiencies (PCE), low energypayback time(EPBT), and low manufacturing costs render perovskite solar cells(PSCs) competitive; however, a relatively low operational stabilityimpedes their large-scale deployment. In addition, state-of- ...

AMER CHEMICAL SOC2023

Bulk and surface engineering to improve performance and stability of perovskite solar cells

Thomas Paul Baumeler

Human society is craving new and renewable energy sources. Indeed, the need for novel sources is an obligation in order to cope with the exponentially increasing global energy demand. Also, environmentally friendly alternatives to fossil fuels are more cru ...

EPFL2022

Efficient and Stable Large Bandgap MAPbBr(3) Perovskite Solar Cell Attaining an Open Circuit Voltage of 1.65 V

Michael Graetzel, Shaik Mohammed Zakeeruddin, Thomas Paul Baumeler, David Lyndon Emsley, Linfeng Pan, Anwar Qasem M Alanazi, Yuhang Liu, Jing Gao, Felix Thomas Eickemeyer, Hongwei Zhu, Michael Allan Hope, Olivier Ouellette

We report on the preparation of MAPbBr(3) perovskite films of high electronic quality by applying a methylamine (MA) vapor treatment and mitigating surface defects using the amphiphilic molecular passivator, neopentylammonium chloride (NPACl). We find that ...

2022

Methylammonium Triiodide for Defect Engineering of High-Efficiency Perovskite Solar Cells

Michael Graetzel, Jacques-Edouard Moser, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Ursula Röthlisberger, Ulf Anders Hagfeldt, Thomas Paul Baumeler, Linfeng Pan, Paramvir Ahlawat, Claudia Esther Avalos, Essa Awadh R Alharbi, Pascal Alexander Schouwink, George Cameron Fish, Mathias Dankl, Bowen Yang, Felix Thomas Eickemeyer, Viktor Skorjanc, Anurag Krishna, Olivier Ouellette, Elsa John, Lukas Pfeifer

The defects present in metal halide perovskite are deleterious to both the performance and stability of photovoltaic devices. Consequently, there is an intense focus on developing defect mitigation strategies. Herein we report a facile strategy that employ ...

2021

Quantifying Stabilized Phase Purity in Formamidinium-Based Multiple-Cation Hybrid Perovskites

Michael Graetzel, Shaik Mohammed Zakeeruddin, Thomas Paul Baumeler, Mohammad Ibrahim Dar, Neha Arora

A promising approach for the production of highly efficient and stable hybrid perovskite solar cells is employing mixed-ion materials. Remarkable performances have been reached by materials comprising a stabilized mixture of methylammonium (MA(+)) and form ...

2021

Formation of High-Performance Multi-Cation Halide Perovskites Photovoltaics by delta-CsPbI3/delta-RbPbI3 Seed-Assisted Heterogeneous Nucleation

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Ulf Anders Hagfeldt, Thomas Paul Baumeler, Linfeng Pan, Essa Awadh R Alharbi, Zaiwei Wang, Masaud Hassan S Almalki, Bowen Yang, Felix Thomas Eickemeyer, Anurag Krishna, Olivier Ouellette

The performance of perovskite solar cells is highly dependent on the fabrication method; thus, controlling the growth mechanism of perovskite crystals is a promising way towards increasing their efficiency and stability. Herein, a multi-cation halide compo ...

2021

Cyclopentadiene-Based Hole-Transport Material for Cost-Reduced Stabilized Perovskite Solar Cells with Power Conversion Efficiencies Over 23%

Michael Graetzel, Shaik Mohammed Zakeeruddin, Thomas Paul Baumeler, Michael Bauer, Yuhang Liu, Felix Thomas Eickemeyer, Hongwei Zhu

Hole transport materials (HTM) are an important component in perovskite solar cells (PSC). Despite a multitude of HTMs developed in recent years, only few of them lead to solar cells with efficiencies over 20%. Therefore, it is still a challenge to develop ...

2021

Minimizing the Trade-Off between Photocurrent and Photovoltage in Triple-Cation Mixed-Halide Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mojtaba Abdi Jalebi, Thomas Paul Baumeler, Mohammad Ibrahim Dar, Neha Arora, Ryusuke Uchida, Yuhang Liu, Seckin Akin

Its lower bandgap makes formamidinium lead iodide (FAPbI(3)) a more suitable candidate for single-junction solar cells than pure methylammonium lead iodide (MAPbI(3)). However, its structural and thermodynamic stability is improved by introducing a signifi ...

2020

Low-Cost and Highly Efficient Carbon-Based Perovskite Solar Cells Exhibiting Excellent Long-Term Operational and UV Stability

Michael Graetzel, Shaik Mohammed Zakeeruddin, Thomas Paul Baumeler, Mohammad Ibrahim Dar, Neha Arora, Ryusuke Uchida, Yuhang Liu, Seckin Akin

Today's perovskite solar cells (PSCs) mostly use components, such as organic hole conductors or noble metal back contacts, that are very expensive or cause degradation of their photovoltaic performance. For future large-scale deployment of PSCs, these comp ...

2019