Publications de Heewon Bahng | EPFL Graph Search

A tandem redox system with a cobalt complex and 2-azaadamantane-N-oxyl for fast dye regeneration and open circuit voltages exceeding 1 V

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jacques-Edouard Moser, Nikolaos Vlachopoulos, Ulf Anders Hagfeldt, Heewon Bahng, Natalie Flores Diaz

A new tandem electrolyte composed of two redox pairs, the organic radical 2-azaadamantane-N-oxyl (AZ) and the well-known redox pair Co(bpy)(3) was investigated in dye sensitized solar cells. Importantly, an increase in V-OC was achieved using the ...

Royal Society of Chemistry2019

Photoinduced Charge Transfer Dynamics in Blue-Coloured Diketopyrrolopyrrole (DPP) Dye-Sensitized Solar Cells

Heewon Bahng

The inception of push-pull organic dyes utilizing the donor-pi conjugated bridge-acceptor (D-pi-A) motif has created a paradigm shift in the design of efficient nanocrystalline dye-sensitized solar cells (DSSCs), offering control over aesthetic and perform ...

EPFL2019

Lateral Intermolecular Electronic Interactions of Diketopyrrolopyrrole D−π–A Solar Dye Sensitizers Adsorbed on Mesoporous Alumina

Jacques-Edouard Moser, Ulf Anders Hagfeldt, Heewon Bahng

The development of push−pull organic dyes utilizing the donor−(π-conjugated bridge)−acceptor (D−π−A) motif has induced a paradigm shift in the design of efficient nanocrystalline dye-sensitized solar cells (DSSCs), offering control over the aesthetic prope ...

2018

Donor Effect on the Photoinduced Interfacial Charge Transfer Dynamics of D−π–A Diketopyrrolopyrrole Dye Sensitizers Adsorbed on Titanium Dioxide

Jacques-Edouard Moser, Ulf Anders Hagfeldt, Heewon Bahng

In this report, we investigate the effects of a strong electron-donating group on the electron injection and recombination processes of diketopyrrolopyrrole (DPP)-sensitized TiO2 films by comparing the dynamics of triphenylamine donor-installed DPP_A and d ...

2018

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

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

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