Publications by Hongwei Zhu | EPFL Graph Search

Related publications (18)

Ti-1-graphene single-atom material for improved energy level alignment in perovskite solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Zaiwei Wang, Felix Thomas Eickemeyer, Hongwei Zhu

Carbon-based perovskite solar cells (C-PSCs) are widely accepted as stable, cost-effective photovoltaics. However, C-PSCs have been suffering from relatively low power conversion efficiencies (PCEs) due to severe electrode-related energy loss. Herein, we r ...

2021

Interface modification to achieve high-efficiency and stable perovskite solar cells

Linfeng Pan, Yuhang Liu, Hongwei Zhu, Zhongjin Shen

The organic-inorganic hybrid perovskite solar cells (PSCs) achieve relatively high power conversion efficiencies (PCEs) over the past few years. However, defects on the surface and at the grain boundaries of the perovskite active layers are critical factor ...

ELSEVIER SCIENCE SA2022

Synergistic Effect of Fluorinated Passivator and Hole Transport Dopant Enables Stable Perovskite Solar Cells with an Efficiency Near 24%

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Linfeng Pan, Yuhang Liu, Felix Thomas Eickemeyer, Yameng Ren, Hongwei Zhu, Olivier Ouellette

Long-term durability is critically important for the commercialization of perovskite solar cells (PSCs). The ionic character of the perovskite and the hydrophilicity of commonly used additives for the hole-transporting layer (HTL), such as lithium bis(trif ...

2021

Low-Cost Dopant Additive-Free Hole-Transporting Material for a Robust Perovskite Solar Cell with Efficiency Exceeding 21%

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Linfeng Pan, Yuhang Liu, Felix Thomas Eickemeyer, Yameng Ren, Hongwei Zhu, Zhongjin Shen

Developing hole-transporting materials (HTMs) with appropriate molecular configuration and charge mobility is important to improve perovskite solar cell (PSC) photovoltaic performance and their feasibility for commercialization. In this work, a novel pyram ...

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

Methylamine Gas Treatment Affords Improving Semitransparency, Efficiency, and Stability of CH3NH3PbBr3-Based Perovskite Solar Cells

Michael Graetzel, Hongwei Zhu

High bandgap semitransparent solar cells based on CH3NH3PbBr3 perovskites are attractive for building integration, tandem cells, and electrochemical applications. The lack of control of the CH3NH3PbBr3 perovskite growth limit the exploitation of CH3NH3PbBr ...

WILEY-V C H VERLAG GMBH2021

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

Thermophysical and thermomechanical properties of basalt-phenolic FRP rebars under high temperature

Thomas Keller, Hongwei Zhu

An experimental investigation was conducted on the thermophysical and thermomechanical properties of phenolic-basalt fiber-reinforced polymer (P-BFRP) rebars subjected to high temperature. As a comparison, vinylBFRP (V-BFRP) and epoxy-BFRP (E-BFRP) rebars ...

ELSEVIER SCI LTD2022

Macrophage NCOR1 Deficiency Ameliorates Myocardial Infarction and Neointimal Hyperplasia in Mice

Johan Auwerx, Hongwei Zhu, Yan Liu

Background NCOR1 (nuclear receptor corepressor 1) is an essential coregulator of gene transcription. It has been shown that NCOR1 in macrophages plays important roles in metabolic regulation. However, the function of macrophage NCOR1 in response to myocard ...

2020

Stabilization of Highly Efficient and Stable Phase-Pure FAPbI(3)Perovskite Solar Cells by Molecularly Tailored 2D-Overlayers

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Mohammad Ibrahim Dar, Jiyoun Seo, Yuhang Liu, Seckin Akin, Felix Thomas Eickemeyer, Hong Zhang, Hongwei Zhu

As a result of their attractive optoelectronic properties, metal halide APbI(3)perovskites employing formamidinium (FA(+)) as the A cation are the focus of research. The superior chemical and thermal stability of FA(+)cations makes alpha-FAPbI(3)more suita ...

Wiley-VCH Verlag GmbH2020

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, 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

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

Molecularly Tailored Surface Defect Modifier for Efficient and Stable Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Yelin Hu, Hongwei Zhu, Zhongjin Shen, Jialin Wang

Surface defects cause non-radiative charge recombination and reduce the photovoltaic performance of perovskite solar cells (PSCs), thus effective passivation of defects has become a crucial method for achieving efficient and stable devices. Organic ammoniu ...

WILEY-V C H VERLAG GMBH2023

CNT-based bifacial perovskite solar cells towards highly efficient 4-terminal tandem photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Fan Fu, Hongwei Zhu, Chunyang Zhang

Carbon-based perovskite solar cells (C-PSCs) are recognized as low-cost stable photovoltaics. However, currently most highly efficient C-PSCs are optically opaque, which means that they can only utilize direct illumination but cannot efficiently utilize th ...

2022

Over 20% PCE perovskite solar cells with superior stability achieved by novel and low-cost hole-transporting materials

Michael Graetzel, Shaik Mohammed Zakeeruddin, Norman Pellet, Chenyi Yi, Xiong Li, Jingshan Luo, Dongqin Bi, Fei Zhang, Hongwei Zhu

The exploration of alternative low-cost molecular hole-transporting materials (HTMs) for both highly efficient and stable perovskite solar cells (PSCs) is a relatively new research area. Two novel HTMs using the thiophene core were designed and synthesized ...

Elsevier Science Bv2017

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

A Smooth CH3NH3PbI3 Film via a New Approach for Forming the PbI2 Nanostructure Together with Strategically High CH3NH3I Concentration for High Efficient Planar-Heterojunction Solar Cells

Michael Graetzel, Hong Zhang, Hongwei Zhu

The photovoltaic performance of perovskite solar cells (PVSCs) is extremely dependent on the morphology and crystallization of the perovskite film, which is affected by the deposition method. In this work, a new approach is demonstrated for forming the PbI ...

Wiley-VCH Verlag Berlin2015

Efficient Perovskite Solar Cell Modules with High Stability Enabled by Iodide Diffusion Barriers

Michael Graetzel, Hongwei Zhu

Operational stability of efficient opto-electronic conversion is crucial for the success in large-scale application of perovskites devices. Owing to the intrinsically weak structure of perovskites, iodide represents the most volatile constituents, and its ...

CELL PRESS2019