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Dan Ren

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Related publications (43)

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Realizing High-Efficiency Perovskite Solar Cells by Passivating Triple-Cation Perovskite Films

Dan Ren, Hongwei Zhu

The photovoltaic performance of perovskite solar cells (PSCs) prepared by the low-temperature solution method has made rapid progress. However, the surface of the film is prone to defects that trap photogenerated charges, resulting in nonradiative recombin ...

WILEY-V C H VERLAG GMBH2022

Carbazol-phenyl-phenothiazine-based sensitizers for dye-sensitized solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Dan Ren, Felix Thomas Eickemeyer, Zhongjin Shen, Lukas Pfeifer

Heteroaromatic units are commonly used as pi-spacers for sensitizers in dye-sensitized solar cells (DSSCs). Here, we investigated the influence of the pi-spacer on the photophysical properties, electrochemical properties and photovoltaic performance of car ...

Royal Society of Chemistry2021

Understanding the electrochemical reduction of carbon dioxide at copper surfaces

Michael Graetzel, Dan Ren

AMER CHEMICAL SOC2018

Boosting Interfacial Electron Transfer and CO2 Enrichment on ZIF-8/ZnTe for Selective Photoelectrochemical Reduction of CO2 to CO

Michael Graetzel, Shaik Mohammed Zakeeruddin, Dan Ren

Artificial photosynthesis is an effective way of converting CO2 into fuel and high value-added chemicals. However, the sluggish interfacial electron transfer and adsorption of CO2 at the catalyst surface strongly hamper the activity and selectivity of CO2 ...

2024

Investigation of nickel iron layered double hydroxide for water oxidation in different pH electrolytes

Michael Graetzel, Lichen Bai, Dan Ren

Nickel iron layered double hydroxide (NiFe LDH) is one of the best oxygen evolution reaction (OER) catalysts in alkaline electrolytes. However, it performs poorly in neutral electrolytes, and the detailed mechanism is still unclear. Herein, we introduce el ...

ELSEVIER2023

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

Spectroelectrochemical and Chemical Evidence of Surface Passivation at Zinc Ferrite (ZnFe 2 O 4 ) Photoanodes for Solar Water Oxidation

Michael Graetzel, Mounir Driss Mensi, Kevin Sivula, Nestor Guijarro Carratala, Liang Yao, Yongpeng Liu, Dan Ren, Meng Xia

Recent advances in low‐cost manufacturing as well as in bulk/interface engineering have positioned zinc ferrite (ZnFe2O4, ZFO) in the spotlight as a candidate material for solar water oxidation. However, the severe recombination at the reactive interface r ...

2021

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, Linfeng Pan, Paramvir Ahlawat, Viacheslav Bolnykh, Dan Ren, Masaud Hassan S Almalki, Hong Zhang, Anurag Krishna

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

Efficient and stable noble-metal-free catalyst for acidic water oxidation

Michael Graetzel, Dan Ren, Jun Li

Developing non-noble catalysts with superior activity and durability for oxygen evolution reaction (OER) in acidic media is paramount for hydrogen production from water. Still, challenges remain due to the inadequate activity and stability of the OER catal ...

Nature Portfolio2022

High carrier mobility along the [111] orientation in Cu2O photoelectrodes

Michael Graetzel, Paul Joseph Dyson, Ulf Anders Hagfeldt, Linfeng Pan, Lu Chen, Dan Ren, Meng Xia, Wenzhe Niu

Solar fuels offer a promising approach to provide sustainable fuels by harnessing sunlight(1,2). Following a decade of advancement, Cu2O photocathodes are capable of delivering a performance comparable to that of photoelectrodes with established photovolta ...

Nature Portfolio2024

Solar reduction of carbon dioxide on copper-tin electrocatalysts with energy conversion efficiency near 20%

Michael Graetzel, Shaik Mohammed Zakeeruddin, Yuhang Liu, Dan Ren, Jing Gao, Meng Xia, Jun Li

Solar-driven carbon dioxide reduction has witnessed a renaissance in the past decades, but the system suffers from low reaction rates. Here the authors develop a copper/tin-oxide electrocatalyst, achieving a new benchmark solar-to-CO energy conversion effi ...

Nature Portfolio2022

Photoelectrocatalytic arene C–H amination

Xile Hu, Laurent Liardet, Jingshan Luo, Lei Zhang, Dan Ren

Photoelectrochemical cells are widely studied for solar energy conversion. However, they have rarely been used for the synthesis of high added-value organic molecules. Here we describe a strategy to use haematite, an abundant and robust photoanode, for non ...

2019

Benzylammonium‐Mediated Formamidinium Lead Iodide Perovskite Phase Stabilization for Photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Dominik Józef Kubicki, David Lyndon Emsley, Zaiwei Wang, Anwar Qasem M Alanazi, Jovana Milic, Dan Ren, Masaud Hassan S Almalki, Aditya Mishra, Felix Thomas Eickemeyer, Hong Zhang

There is an ongoing surge of interest in the use of formamidinium (FA) lead iodide perovskites in photovoltaics due to their exceptional optoelectronic properties. However, thermodynamic instability of the desired cubic perovskite (α-FAPbI3) phase at ambie ...

2021

Guanine‐Stabilized Formamidinium Lead Iodide Perovskites

Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Amita Ummadisingu, Marko Mladenovic, Dominik Józef Kubicki, David Lyndon Emsley, Linfeng Pan, Paramvir Ahlawat, Yuhang Liu, Jovana Milic, Dan Ren, Marco Alejandro Ruiz Preciado

Formamidinium (FA) lead iodide perovskite materials feature promising photovoltaic performances and superior thermal stabilities. However, conversion of the perovskite α‐FAPbI3 phase to the thermodynamically stable yet photovoltaically inactive δ‐FAPbI3 ph ...

2020

Thiocyanate-Mediated Dimensionality Transformation of Low- Dimensional Perovskites for Photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Claudia Esther Avalos, Zaiwei Wang, Yuhang Liu, Brian Irving Carlsen, Jovana Milic, Dan Ren

Two-dimensional (2D) hybrid perovskite solar cells have induced widespread research interest owing to their higher stability as compared to three-dimensional (3D) analogues. The photovoltaic performance, however, is still limited. Here, we report a perovsk ...

2022

Atomic-Level Microstructure of Efficient Formamidinium-Based Perovskite Solar Cells Stabilized by 5-Ammonium Valeric Acid Iodide Revealed by Multinuclear and Two-Dimensional Solid-State NMR

Michael Graetzel, Jacques-Edouard Moser, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Marine Eva Fedora Bouduban, Marko Mladenovic, Fabrizio Giordano, Dominik Józef Kubicki, David Lyndon Emsley, Farzaneh Jahanbakhshi, Essa Awadh R Alharbi, Daniel Prochowicz, Anwar Qasem M Alanazi, Jovana Milic, Dan Ren

Chemical doping of inorganic–organic hybrid perovskites is an effective way of improving the performance and operational stability of perovskite solar cells (PSCs). Here we use 5-ammonium valeric acid iodide (AVAI) to chemically stabilize the structure of ...

2019

Regulated CO adsorption by the electrode with OH− repulsive property for enhancing C–C coupling

Michael Graetzel, Mingkui Wang, Jingshan Luo, Dan Ren, Jing Gao, Jialin Wang, Minhuan Wang

Electrochemical CO2 reduction driven by renewable electricity is one of the promising strategies to store sustainable energy as fuels. However, the selectivity of value-added multi-carbon products remains poor for further application of this process. Here, ...

2023

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, 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

Atomic Layer Deposition of ZnO on CuO Enables Selective and Efficient Electroreduction of Carbon Dioxide to Liquid Fuels

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Jingshan Luo, Linfeng Pan, Zaiwei Wang, Dan Ren, Jing Gao

Electrochemical reduction of carbon dioxide, if powered by renewable electricity, could serve as a sustainable technology for carbon recycling and energy storage. Among all the products, ethanol is an attractive liquid fuel. However, the maximum faradaic e ...

Wiley-VCH Verlag GmbH2019

Tailored Amphiphilic Molecular Mitigators for Stable Perovskite Solar Cells with 23.5% Efficiency

Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Mohammad Ibrahim Dar, Xiong Li, Linfeng Pan, Zaiwei Wang, Yuhang Liu, Brian Irving Carlsen, Dan Ren, Marco Alejandro Ruiz Preciado, Bowen Yang, Felix Thomas Eickemeyer, Hongwei Zhu

Passivation of interfacial defects serves as an effective means to realize highly efficient and stable perovskite solar cells (PSCs). However, most molecular modulators currently used to mitigate such defects form poorly conductive aggregates at the perovs ...

Wiley2020