Publications de Xiaoyu Zhang | EPFL Graph Search

Phase-stable indium sulfide achieves an energy conversion efficiency of 14.3% for solar-assisted carbon dioxide reduction to formate

Michael Graetzel, Jingshan Luo, Xiaoyu Zhang, Jing Gao, Qixing Zhang, Jun Li

Tremendous efforts have been made in developing highly selective catalysts for electrochemical CO 2 conversion to formate. However, the rapid deactivation resulting from structural reconstruction and phase transition poses considerable challenges to the sy ...

Cell Press2024

Suppressed recombination for monolithic inorganic perovskite/silicon tandem solar cells with an approximate efficiency of 23%

Michael Graetzel, Peng Wang, Xiaoyu Zhang, Yang Li, Shilong Wang

Potentially temperature-resistant inorganic perovskite/silicon tandem solar cells (TSCs) are promising devices for boosting efficiency past the single-junction silicon limit. However, undesirable non-radiative recombination generally leads to a significant ...

Keai Publishing Ltd2022

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

Michael Graetzel, Mingkui Wang, Jingshan Luo, Xiaoyu Zhang, Dan Ren, Jing Gao, Qixing Zhang, Jialin 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

Micro-Electrode with Fast Mass Transport for Enhancing Selectivity of Carbonaceous Products in Electrochemical CO2 Reduction

Michael Graetzel, Mingkui Wang, Jingshan Luo, Xiaoyu Zhang, Dan Ren, Qixing Zhang

During electrochemical carbon dioxide (CO2) reduction on copper electrodes in an aqueous electrolyte, one of the key challenges is the competition between hydrogen evolution and CO2 reduction, especially under large current density. Here, micro-electrodes ...

2021

Ligand-Modulated Excess PbI2 Nanosheets for Highly Efficient and Stable Perovskite Solar Cells

Ulf Anders Hagfeldt, Chenyi Yi, Yi Ding, Jingshan Luo, Xiaoyu Zhang, Zaiwei Wang, Zhen Yang

Excess lead iodide (PbI2), as a defect passivation material in perovskite films, contributes to the longer carrier lifetime and reduced halide vacancies for high-efficiency perovskite solar cells. However, the random distribution of excess PbI2 also leads ...

Wiley-V C H Verlag Gmbh2020

Quasi-Heteroface Perovskite Solar Cells

Ulf Anders Hagfeldt, Yi Ding, Peng Wang, Xiaoyu Zhang, Yang Li

Perovskite solar cells (PSCs) have attracted unprecedented attention due to their rapidly rising photoelectric conversion efficiency (PCE). In order to further improve the PCE of PSCs, new possible optimization path needs to be found. Here, quasi-heterofac ...

WILEY-V C H VERLAG GMBH2020

Guanidinium-Assisted Surface Matrix Engineering for Highly Efficient Perovskite Quantum Dot Photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jiabao Yang, Xiaoyu Zhang, Xufeng Ling, Chunyang Zhang, Wanli Ma

Metal halide perovskite quantum dots (Pe-QDs) are of great interest in new-generation photovoltaics (PVs). However, it remains challenging in the construction of conductive and intact Pe-QD films to maximize their functionality. Herein, a ligand-assisted s ...

Wiley2020

Ti/Co-S catalyst covered amorphous Si-based photocathodes with high photovoltage for the HER in non-acid environments

Jingshan Luo, Xiaoyu Zhang, Qixing Zhang

Royal Society of Chemistry2018

Dye-sensitized solar cells for efficient power generation under ambient lighting

Paul Liska, Jacques-Edouard Moser, Shaik Mohammed Zakeeruddin, Joël Teuscher, Ulf Anders Hagfeldt, Fabrizio Giordano, Yasemin Saygili, Xiaoyu Zhang, Marina Freitag

Solar cells that operate efficiently under indoor lighting are of great practical interest as they can serve as electric power sources for portable electronics and devices for wireless sensor networks or the Internet of Things. Here, we demonstrate a dye-s ...

Nature Publishing Group2017

Elucidating the role of chlorine in perovskite solar cells

Ulf Anders Hagfeldt, Li Fan, Yi Ding, Jingshan Luo, Xiaoyu Zhang, Di Zhang, Gang Wang

It has been proposed that introducing the chlorine anion into a CH3NH3PbI3 perovskite material can substantially improve the materials properties as well as the solar cell performance. To elucidate the role of chlorine in perovskite solar cells (PSCs), her ...

Royal Society of Chemistry2017

Significance of pi-bridge contribution in pyrido[3,4-b]pyrazine featured D-A-pi-A organic dyes for dye-sensitized solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Yelin Hu, Fabrizio Giordano, Xiaoyu Zhang, Zhongjin Shen

The 3,4-ethylenedioxythiophene (EDOT) pi-bridge is one of the most commonly used building blocks for sensitizers in dye-sensitized solar cells (DSSCs). We investigated its influence on the molecular structure, the photophysical and electrochemical properti ...

Chinese Chemical Soc2017

Hydrogenated TiO2 Thin Film for Accelerating Electron Transport in Highly Efficient Planar Perovskite Solar Cells

Yi Ding, Jingshan Luo, Xiaoyu Zhang, Di Zhang, Yang Li

Intensive studies on low-temperature deposited electron transport materials have been performed to improve the efficiency of n-i-p type planar perovskite solar cells to extend their application on plastic and multijunction device architectures. Here, a TiO ...

2017

Enhanced light absorption of thin perovskite solar cells using textured substrates

Li Fan, Yi Ding, Jingshan Luo, Xiaoyu Zhang, Di Zhang, Yang Li

Thin perovskite layers are crucial for fabricating semitransparent perovskite solar cells and tandem devices. However, this will reduce the light absorption of the device, resulting in low efficiency. To overcome this dilemma, we use textured fluorine dope ...

Elsevier Science Bv2017

Molecular Engineering of Potent Sensitizers for Very Efficient Light Harvesting in Thin-Film Solid-State Dye-Sensitized Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Marcel Roland Schreier, Norman Pellet, Chenyi Yi, Yelin Hu, Fabrizio Giordano, Xiaoyu Zhang, Yi Xu

Dye-sensitized solar cells (DSSCs) have shown significant potential for indoor arid building integrated photovoltaic applications. Herein we present three new D-A-pi-A organic sensitizers, XY1, XY2, and XY3, that exhibit high molar extinction coefficients ...

Amer Chemical Soc2016

Donor design and modification strategies of metal-free sensitizers for highly-efficient n-type dye-sensitized solar cells

Michael Graetzel, Xiaoyu Zhang

Dye-sensitized solar cells (DSSCs) cannot be developed without the research on sensitizers. As the key of light harvesting and electron generation, thousands of sensitizers have been designed for the application in DSSC devices. Among them, organic sensiti ...

Higher Education Press2016

Cyclometalated Iridium(III) Complexes Based on Phenyl-Imidazole Ligand

Michael Graetzel, Mohammad Khaja Nazeeruddin, Rosario Scopelliti, Xiaoyu Zhang, Filippo de Angelis

Phenyl-imidazole-based ligands with various substitution patterns have been used as the main ligand for heteroleptic bis-cyclometalated Iridium complexes. Two series of complexes have been prepared and their photophysical and electrochemical properties wer ...

2011

Dye-sensitized solar cells based on poly (3,4-ethylenedioxythiophene) counter electrode derived from ionic liquids

Michael Graetzel, Mohammad Khaja Nazeeruddin, Jun Ho Yum, Xiaoyu Zhang

Poly (3,4-ethylenedioxythiophene) (PEDOT) nanoporous layers were prepared with electro-oxidative polymerization using room temperature hydrophobic ionic liquids as a medium. The synthesized highly porous PEDOT films exhibit room temperature conductivity va ...

Royal Society of Chemistry2010

Theoretical Screening of -NH2-, -OH-, -CH3-, -F-, and -SH-Substituted Porphyrins As Sensitizer Candidates for Dye-Sensitized Solar Cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Xiaoyu Zhang

Following former Studies, the donor-acceptor combinations of -NH2-substituted porphyrin donor and the acceptors C, D, E, F, H and G, those of -OH-, -CH3- and -Ph-substituted porphyrins as well as porphine donors and the acceptors E, G. and H, and those of ...

American Chemical Society2010

Substituent Effect on the Meso-Substituted Porphyrins: Theoretical Screening of Sensitizer Candidates for Dye-Sensitized Solar Cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Xiaoyu Zhang

According to the concepts of attribute axis and attribute coordinate system, porphine and 11 kinds of bridge carbon substituted porphyrins as donors and 9 common acceptors A-I have been designed and calculated at the density functional B3LYP level. The sub ...

2009

Functionalized alkyne bridged dendron based chromophores for dye-sensitized solar cell applications

Michael Graetzel, Mohammad Khaja Nazeeruddin, Jun Ho Yum, Xiaoyu Zhang

We report the results of an investigation on the preparation, spectral and photoelectrochemical properties of alkyne bridged dendron chromophores with carboxylic acid anchoring group, which adhere effectively to nanocrystalline (anatase) TiO2 surfaces yiel ...

2009