A5056124104- TiO2 Photocatalysis and Solar Cells
- Advanced Photocatalysis Techniques
- Advanced Nanomaterials in Catalysis
- Perovskite Materials and Applications
- Quantum Dots Synthesis And Properties
- Fuel Cells and Related Materials
- Conducting polymers and applications
- Electrochemical sensors and biosensors
- Advancements in Solid Oxide Fuel Cells
- Electrocatalysts for Energy Conversion
- Luminescence and Fluorescent Materials
- Electrochemical Analysis and Applications
- Advanced battery technologies research
- Marine Biology and Environmental Chemistry
- Porphyrin and Phthalocyanine Chemistry
École Polytechnique Fédérale de Lausanne
2016-2020
Middle East Technical University
2014
Redox mediators play a major role determining the photocurrent and photovoltage in dye-sensitized solar cells (DSCs). To maintain photocurrent, reduction of oxidized dye by redox mediator should be significantly faster than electron back transfer between TiO2 dye. The driving force for regeneration with sufficiently low to provide high photovoltages. With introduction our new copper complexes as promising DSCs both criteria are satisfied enhance power conversion efficiencies. In this study,...
Abstract Solid-state dye-sensitized solar cells currently suffer from issues such as inadequate nanopore filling, low conductivity and crystallization of hole-transport materials infiltrated in the mesoscopic TiO 2 scaffolds, leading to performances. Here we report a record 11% stable solid-state cell under standard air mass 1.5 global using material composed blend [Cu (4,4′,6,6′-tetramethyl-2,2′-bipyridine) ](bis(trifluoromethylsulfonyl)imide) ](bis(trifluoromethylsulfonyl)imide). The...
The unprecedentedly targeted down-regulation of <italic>V</italic><sub>loss</sub> in DSSCs renders a power conversion efficiency 11.7% for solid-state DSSCs.
Abstract Rapid extraction of photogenerated charge carriers is essential to achieve high efficiencies with perovskite solar cells (PSCs). Here, a new mesoscopic architecture as electron‐selective contact for PSCs featuring 40 nm sized TiO 2 beads endowed mesopores few nanometer diameters introduced. The bimodal pore distribution inherent these films produces very large area 200 m g −1 whose access by the light absorber facilitated interstitial voids between particles. Modification surface...
Photoelectrochemical approach to solar energy conversion demands a kinetic optimization of various light-induced electron transfer processes. Of great importance are the redox mediator systems accomplishing processes at semiconductor/electrolyte interface, therefore affecting profoundly performance photoelectrochemical cells. Here, we develop strategy-by addition small organic donor, tris(4-methoxyphenyl)amine, into state-of-art cobalt tris(bipyridine) electrolyte-to significantly improve...
Dye-sensitized solar cells (DSSCs) have attracted a substantial interest in the last 30 years for conversion of power to electricity. An important component is redox mediator effecting transport charge between photoelectrode and dark counter electrode (CE). Among possible mediators, metal coordination complexes play prominent role at present are incorporated several types devices with efficiency exceeding 10%. The review, after brief introduction operation DSSCs, discusses first requirements...
Blue and green dyes as well NIR-absorbing have attracted great interest because of their excellent ability absorbing the incident photons in red near-infrared range region. A novel blue D−π–A dye (Dyenamo Blue), based on diketopyrrolopyrrole (DPP)-core, has been designed synthesized. Assembled with cobalt bipyridine-based electrolytes, device Dyenamo achieved a satisfying efficiency 7.3% under one sun (AM1.5 G). The co-sensitization strategy was further applied this organic together (D35)....
Abstract The synthesis, characterization, and photovoltaic performance of a series indacenodithiophene (IDT)‐based D ‐π‐A organic dyes with varying electron‐accepting units is presented. By control the electron affinity, perfectly matching energy levels were achieved copper(I/II)‐based redox electrolyte, reaching high open‐circuit voltage (>1.1 V) while harvesting large fraction solar photons at same time. Besides achieving power conversion efficiencies (PCEs) for dye‐sensitized cells...
The recombination of injected electrons with oxidized redox species and regeneration behavior copper mediators are investigated for four complexes, [Cu(dmby)2]2+/1+ (dmby = 6,6′-dimethyl-2,2′-bipyridine), [Cu(tmby)2]2+/1+ (tmby 4,4′,6,6′- tetramethyl-2,2′-bipyridine), [Cu(eto)2]2+/1+ (eto 4-ethoxy-6,6′-dimethyl-2,2′-bipyridine), [Cu(dmp)2]2+/1+ (dmp bis(2,9-dimethyl-1,10-phenantroline). These complexes were examined in conjunction the D5, D35, D45 sensitizers, having various degrees blocking...
A metal-free organic sensitizer, suitable for the application in dye-sensitized solar cells (DSSCs), has been designed, synthesized and characterized both experimentally theoretically. The structure of novel donor-acceptor-π-bridge-acceptor (D-A-π-A) dye incorporates a triphenylamine (TPA) segment 4-(benzo[c][1,2,5]thiadiazol-4-ylethynyl)benzoic acid (BTEBA). unit is widely used as an electron donor photosensitizers, owing to its nonplanar molecular configuration excellent electron-donating...
Two new metal-free organic sensitizers, L156 and L224, were designed, synthesized, characterized for application in dye-sensitized solar cells (DSCs). The structures of the dyes contain a triphenylamine (TPA) segment 4-(benzo[c][1,2,5]thiadiazol-4-yl)benzoic acid as electron-rich -deficient moieties, respectively. different π bridges, thiophene 4,8-bis(4-hexylphenyl)benzo[1,2-b:4,5-b']dithiophene, used influence iodide/triiodide, [Co(bpy)3 ]2+/3+ (bpy=2,2'-bipyridine), [Cu(tmby)2 ]2+/+...
In this study, a new mechanism for doping of spiro-MeOTAD by Zn(TFSI)2 is revealed, which completely different from the induced LiTFSI. The oxidation facilitated complexation between zinc cation and tert-butylpyridine (tBP) even in absence oxygen light. lone electron pair nitrogen tBP coordinates to cation, confirmed Fourier transform infrared spectroscopy peak at 1637 cm–1 corresponding pyridine ring mode coupled with coordinating as Lewis site. also evidenced computational calculations....
Copper redox mediators can be employed in dye sensitized solar cells (DSCs) both as liquid electrolytes or solid state hole transport materials (HTMs). The devices that employ copper complex HTMs simply obtained by solvent evaporation devices. During this evolution, the molecules present electrolyte slowly aggregate pores of TiO2 film and also close gap between counter electrode. However, crystallization HTM infiltrated mesoscopic lead to low photovoltaic performance. In order prevent...
Abstract The synthesis, characterization, and photovoltaic performance of a series indacenodithiophene (IDT)‐based D ‐π‐A organic dyes with varying electron‐accepting units is presented. By control the electron affinity, perfectly matching energy levels were achieved copper(I/II)‐based redox electrolyte, reaching high open‐circuit voltage (>1.1 V) while harvesting large fraction solar photons at same time. Besides achieving power conversion efficiencies (PCEs) for dye‐sensitized cells...
In perovskite solar cells (PSCs), the most commonly used hole transport material (HTM) is spiro-OMeTAD, which typically doped by metalorganic complexes, for example, based on Co, to improve charge properties and thereby enhance photovoltaic performance of device. this study, we report a new hemicage-structured iron complex, 1,3,5-tris(5'-methyl-2,2'-bipyridin-5-yl)ethylbenzene Fe(III)-tris(bis(trifluoromethylsulfonyl)imide), as p-type dopant spiro-OMeTAD. The formal redox potential compound...