Publications de Anurag Krishna

Stabilization of highly efficient perovskite solar cells with a tailored supramolecular interface

Michael Graetzel, Shaik Mohammed Zakeeruddin, David Lyndon Emsley, Masaud Hassan S Almalki, Aditya Mishra, Felix Thomas Eickemeyer, Michael Allan Hope, Anurag Krishna, Zhiwen Zhou, Chenxu Zhao

The presence of defects at the interface between the perovskite film and the carrier transport layer poses significant challenges to the performance and stability of perovskite solar cells (PSCs). Addressing this issue, we introduce a dual host-guest (DHG) ...

Nature Research2024

Quantifying Recombination and Charge Carrier Extraction in Halide Perovskites Via Hyperspectral Time-resolved Photoluminescence Imaging

Anurag Krishna

Identifying sources of nonradiative recombination and quantifying charge carrier extraction in halide perovskite solar cells are important in further developing this thin-film technology. Steady-state and time-resolved photoluminescence (TRPL), in combinat ...

AIP Publishing2024

Graphene-Templated Achiral Hybrid Perovskite for Circularly Polarized Light Sensing

Michael Graetzel, Anurag Krishna, Georgios Kakavelakis

This study points out the importance of the templating effect in hybrid organic-inorganic perovskite semiconductors grown on graphene. By combining two achiral materials, we report the formation of a chiral composite heterostructure with electronic band sp ...

2024

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

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

Stabilization of FAPbI(3) with Multifunctional Alkali-Functionalized Polymer

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jing Gao, Masaud Hassan S Almalki, Felix Thomas Eickemeyer, Hong Zhang, Anurag Krishna

The defects located at the interfaces and grain boundaries (GBs) of perovskite films are detrimental to the photovoltaic performance and stability of perovskite solar cells. Manipulating the perovskite crystallization process and tailoring the interfaces w ...

Wiley-V C H Verlag Gmbh2023

Understanding and decoupling the role of wavelength and defects in light-induced degradation of metal-halide perovskites

Michael Graetzel, Ulf Anders Hagfeldt, Anurag Krishna

Light-induced degradation in metal halide perovskites is a major concern that can potentially hamper the commercialization of perovskite optoelectronic devices. The phenomena viz. ion migration, phase segregation, and defect intolerance are believed to be ...

Royal Soc Chemistry2023

Optoelectronic or photovoltaic device with metal halide perovskite film treated by passivating agent

Michael Graetzel, Shaik Mohammed Zakeeruddin, Essa Awadh R Alharbi, Anurag Krishna, Lukas Pfeifer

This invention relates to an optoelectronic or photovoltaic device comprising a perovskite or metal halide perovskite film treated by one or more compounds of formula (I): ((R1-NH(R2)-R3)+)nW (I), wherein n is an integer selected from 1, 2, or 3; R1, R2, R ...

2023

Mitigating the Heterointerface Driven Instability in Perovskite Photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Essa Awadh R Alharbi, Mathias Dankl, Felix Thomas Eickemeyer, Hong Zhang, Anurag Krishna

Metal halide perovskites have thepotential to revolutionizethefield of photovoltaics, though limited stability has impeded commercialexploitation. The soft heterointerface between the perovskite andcharge-transporting layer is one of the major bottlenecks ...

AMER CHEMICAL SOC2023

A universal co-solvent dilution strategy enables facile and cost-effective fabrication of perovskite photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Sandy Sanchez Alonso, Narges Yaghoobi Nia, Linfeng Pan, Paramvir Ahlawat, Viacheslav Bolnykh, Dan Ren, Masaud Hassan S Almalki, Hong Zhang, Anurag Krishna, Tzu-Sen Su

Cost management and toxic waste generation are two key issues that must be addressed before the commercialization of perovskite optoelectronic devices. We report a ground-breaking strategy for eco-friendly and cost-effective fabrication of highly efficient ...

Nature Research2022

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

Multimodal host–guest complexation for efficient and stable perovskite photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Marko Mladenovic, David Lyndon Emsley, Farzaneh Jahanbakhshi, Paramvir Ahlawat, Zaiwei Wang, Jovana Milic, Dan Ren, Aditya Mishra, Felix Thomas Eickemeyer, Hong Zhang, Zhaowen Dong, Jinming Guo, Michael Allan Hope, Anurag Krishna, Olivier Ouellette, Tzu-Sen Su, Zhiwen Zhou

Formamidinium lead iodide perovskites are promising light-harvesting materials, yet stabilizing them under operating conditions without compromising optimal optoelectronic properties remains challenging. We report a multimodal host–guest complexation strat ...

Nature Research2021

Nanoscale interfacial engineering enables highly stable and efficient perovskite photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Ursula Röthlisberger, Ulf Anders Hagfeldt, Sandy Sanchez Alonso, Mathias Dankl, Hong Zhang, Anurag Krishna, Olivier Ouellette

We present a facile molecular-level interface engineering strategy to augment the long-term operational and thermal stability of perovskite solar cells (PSCs) by tailoring the interface between the perovskite and hole transporting layer (HTL) with a multif ...

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

Combined Precursor Engineering and Grain Anchoring Leading to MA-Free, Phase-Pure, and Stable alpha-Formamidinium Lead Iodide Perovskites for Efficient Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Carole Graetzel, Linfeng Pan, Yuhang Liu, Dan Ren, Jing Gao, Hongwei Zhu, Anurag Krishna, Olivier Ouellette

alpha-Formamidinium lead iodide (alpha-FAPbI(3)) is one of the most promising candidate materials for high-efficiency and thermally stable perovskite solar cells (PSCs) owing to its outstanding optoelectrical properties and high thermal stability. However, ...

Wiley-VCH Verlag GmbH2021

Compositional and Interface Engineering of Organic-Inorganic Lead Halide Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Haizhou Lu, Anurag Krishna

Power conversion efficiency (PCE) of the perovskite solar cells (PSCs) has remarkably been increased from3.1%to 25.2%. The fast expansion of the PSCs has been along with the development of compositional and interface engineering, which has been playing a c ...

2020

Crown Ether Modulation Enables over 23% Efficient Formamidinium-Based Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Ursula Röthlisberger, Ulf Anders Hagfeldt, Jun Ho Yum, Kevin Sivula, Marko Mladenovic, David Lyndon Emsley, Farzaneh Jahanbakhshi, Jovana Milic, Dan Ren, Aditya Mishra, Felix Thomas Eickemeyer, Hong Zhang, Michael Allan Hope, Jun Li, Anurag Krishna, Olivier Ouellette, Zhiwen Zhou

The use of molecular modulators to reduce the defect density at the surface and grain boundaries of perovskite materials has been demonstrated to be an effective approach to enhance the photovoltaic performance and device stability of perovskite solar cell ...

2020

Defect Passivation via the Incorporation of Tetrapropylammonium Cation Leading to Stability Enhancement in Lead Halide Perovskite

Anurag Krishna

Improving the performances of photovoltaic (PV) devices by suppressing nonradiative energy losses through surface defect passivation and enhancing the stability to the level of standard PV represents one critical challenge for perovskite solar cells. Here, ...

WILEY-V C H VERLAG GMBH2020

Mixed Dimensional 2D/3D Hybrid Perovskite Absorbers: The Future of Perovskite Solar Cells?

Mohammad Khaja Nazeeruddin, Anurag Krishna

The cost-effective processability and high efficiency of the organic-inorganic metal halide perovskite solar cells (PSCs) have shown tremendous potential to intervene positively in the generation of clean energy. However, prior to an industrial scale-up pr ...

WILEY-V C H VERLAG GMBH2019