Publications by Weiwei Zhang | EPFL Graph Search

Phenanthrene-Fused-Quinoxaline as a Key Building Block for Highly Efficient and Stable Sensitizers in Copper-Electrolyte-Based Dye-Sensitized Solar Cells

Michael Graetzel, Jacques-Edouard Moser, Shaik Mohammed Zakeeruddin, Etienne Christophe Socie, Weiwei Zhang, Brian Irving Carlsen, Yameng Ren, Huiyun Jiang, Yinghui Wu

Dye-sensitized solar cells (DSSCs) based on Cu-II/I bipyridyl or phenanthroline complexes as redox shuttles have achieved very high open-circuit voltages (V-OC, more than 1 V). However, their short-circuit photocurrent density (J(SC)) has remained modest. ...

Wiley-VCH Verlag GmbH2020

Electron-Affinity-Triggered Variations on the Optical and Electrical Properties of Dye Molecules Enabling Highly Efficient Dye-Sensitized Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Péter Kalman Péchy, Ulf Anders Hagfeldt, Yiming Cao, Marko Stojanovic, Mohammad Ibrahim Dar, Yasemin Saygili, Weiwei Zhang, Yuhang Liu

The synthesis, characterization, and photovoltaic performance of a series of indacenodithiophene (IDT)-based D--A organic dyes with varying electron-accepting units is presented. By control of the electron affinity, perfectly matching energy levels were ac ...

Wiley-VCH Verlag GmbH2018

Comprehensive control of voltage loss enables 11.7% efficient solid-state dye-sensitized solar cells

Jacques-Edouard Moser, Shaik Mohammed Zakeeruddin, Ladislav Kavan, Ulf Anders Hagfeldt, Chenyi Yi, Yiming Cao, Jingshan Luo, Yasemin Saygili, Heewon Bahng, Weiwei Zhang, Yuhang Liu, Yinghui Wu

The relatively large voltage loss (Vloss) in excitonic type solar cells severely limits their power conversion efficiencies (PCEs). Here, we report a comprehensive control of Vloss through efficacious engineering of the sensitizer and redox mediator, makin ...

2018

Analytical Model for Mean Flow and Fluxes of Momentum and Energy in Very Large Wind Farms

Fernando Porté Agel, Corey Dean Markfort, Weiwei Zhang

2018

Exogenous stromal derived factor-1 releasing silk scaffold combined with intra-articular injection of progenitor cells promotes bone-ligament-bone regeneration

Weiliang Shen, Weiwei Zhang, Jiayun Huang

2018

Molecular Design of Efficient Organic D-A-pi-A Dye Featuring Triphenylamine as Donor Fragment for Application in Dye-Sensitized Solar Cells

Shaik Mohammed Zakeeruddin, Ladislav Kavan, Yasemin Saygili, Weiwei Zhang

2018

Solution-Processed Cu2S Photocathodes for Photoelectrochemical Water Splitting

Matthew Thomas Mayer, Jingshan Luo, Minkyu Son, Linfeng Pan, Yuxiang Yu, Weiwei Zhang

2018

The Importance of Pendant Groups on Triphenylamine-Based Hole Transport Materials for Obtaining Perovskite Solar Cells with over 20% Efficiency

Nikolaos Vlachopoulos, Liang Wang, Lin Yang, Peng Liu, Weiwei Zhang, Jiahuan Zhang

2018

Highly efficient dye-sensitized solar cells achieved through using Pt-free Nb2O5/C composite counter electrode and iodide-free redox couples

Ulf Anders Hagfeldt, Weiwei Zhang, Wenyan Li

To improve the catalytic activity of Nb2O5, a composite Nb2O5/C (Nb2O5 imbedded in carbon support) is synthesized with a simple in situ method and then introduced the composite into dye-sensitized solar cells (DSCs) as a counter electrode (CE) catalyst. Ba ...

Elsevier Science Bv2016

Low-cost Cr doped Pt3Ni alloy supported on carbon nanofibers composites counter electrode for efficient dye-sensitized solar cells

Ulf Anders Hagfeldt, Weiwei Zhang, Mei Wang

Pt3Ni alloy supported by carbon nanofibers (CNs) composites (Pt3Ni/CNs) synthesized by a simple solvothermal process was introduced into dye-sensitized solar cells (DSCs) as counter electrode (CE) for the first time, and the DSCs based on Pt3Ni/CNs CE obta ...

Elsevier Science Bv2016

Highly effective Co3S4/electrospun-carbon-nanofibers composite counter electrode synthesized with electrospun technique for cobalt redox electrolyte based on dye-sensitized solar cells

Ulf Anders Hagfeldt, Weiwei Zhang

The composite of cobaltosic sulfide/electrospun carbon nanofibers (Co3S4/ECs) with high catalytic activity have been successfully synthesized by combining the versatility of the electrospunning technique and following a hydrothermal synthesis method. And t ...

Elsevier Science Bv2016

Mesoporous carbon-imbedded W2C composites as flexible counter electrodes for dye-sensitized solar cells

Ulf Anders Hagfeldt, Weiwei Zhang

Mesoporous carbon (MC)-imbedded tungsten carbide (W2C) composites are synthesized via a simple methodology and subsequently used as flexible counter electrodes (CEs) in dye-sensitized solar cells (DSCs). The W2C/MC composite possesses remarkable electroche ...

Royal Society of Chemistry2016

'Low-cost Cr doped Pt3Ni alloy supported on carbon nanofibers composites counter electrode for efficient dye-sensitized solar cells' (vol 328, pg 543, 2016)

Ulf Anders Hagfeldt, Weiwei Zhang, Mei Wang

Elsevier2016

Efficient and stable large-area perovskite solar cells with inorganic charge extraction layers

Michael Graetzel, Wei Chen, Weiwei Zhang, Jian Liu, Yinghui Wu

The recent dramatic rise in power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) has triggered intense research worldwide. However, high PCE values have often been reached with poor stability at an illuminated area of typically less than 0 ...

American Association for the Advancement of Science2015