We designed and synthesized new alkyl-functionalized organic dyes, MK-1 MK-2, for dye-sensitized solar cells (DSSCs). Based on the MK-2 dye, a high performance of efficiency (eta, 7.7%; short-circuit current density Jsc = 14.0 mA cm-2, open-circuit voltage Voc 0.74 V, fill factor FF 0.74) was achieved under AM 1.5 G irradiation (100 mW cm-2). Remarkably, relatively higher DSSCs based which have long alkyl chains, were observed among dyes caused by increasing electron lifetime in conduction...

Three donor−linker−acceptor triphenylamine-based cyanoacrylic acid organic dyes used for dye-sensitized solar cells (DSCs) have been examined with respect to their effect on the open-circuit voltage (Voc). Our previous study showed a decrease in Voc DSCs based increased molecular size (increased linker conjugation). In present study, we investigate origin of (i) conduction band (ECB) positions TiO2 and (ii) degree recombination between electrons electrolyte acceptor species at interface....

Porphyrin molecules offer immense potential as the light harvesting component of dye-sensitised nanocrystalline TiO2 solar cells. Synthetic porphyrin dyes were amongst first trialled for sensitisation inorganic semiconducting oxides. Today, they exhibit best performance reported Accompanying significant improvement over last two decades is a much improved understanding efficiency-determining fundamental electron transfer steps, from charge photogeneration to recombination. In this feature...

Performances of dye-sensitized solar cells prepared from nanoporous TiO2 films with different nanoparticle preparation methods and annealing temperatures are studied various film thicknesses. The results show that the at higher have energy conversion efficiencies. Regarding thickness, thin electrode annealed low-temperature comparable efficiencies those high temperature. difference efficiency between increases thickness. To explain observations, surface area films, amount adsorbed dye,...

Electron diffusion coefficient, lifetime, and density in the TiO(2) electrode of dye-sensitized solar cells (DSCs) employing I(-)/I(3)(-) redox couples were measured with eight different metal-free organic dyes three Ru complex dyes. At matched electron density, all DSCs using (ODSCs) showed shorter lifetime comparable or larger coefficients comparison to (RuDSC). The was attributed partially slower dye cation reduction rate by I(-), faster coefficient TiO(2), mostly higher I(3)(-)...

Enlarging the molecular size of zinc phthalocyanine (Pc) dyes three dimensionally with 2,6-diphenylphenoxy substituents significantly reduced aggregation on a TiO(2) surface. As result, incident photon-to-current conversion efficiency was improved not only in Q band but over whole absorption range, achieving 4.6% energy under one-sun conditions. Electron lifetime measurements indicated that these Pc do enhance charge recombination, encouraging further development Pc.

Zn−Zn porphyrin dimers have been incorporated into thin dye-sensitized solar cells (DSSCs) to boost their light harvesting efficiency. The photoexcited show efficient and fast electron injection TiO2 indicating that both chromophores contribute current generation. improved ability coupled enhanced DSSC performance demonstrates the potential of 3-D arrays as next generation harvesters for artificial energy conversion systems.

We fabricated dye-adsorbed NiO solar cells (pDSCs) with six different metal-free organic dyes having various ground-state oxidation potentials. Under monochromatic light irradiation, all showed cathodic current at wavelengths where the absorb, suggesting hole injection occurred from adsorbed to valence band of NiO. Absorbed photon-to-current conversion efficiency (APCE) tends increase energy difference (ΔE) between edge and ground state dyes. The maximum APCE 30% was obtained 0.6 eV ΔE....

Asymmetric zinc phthalocyanines with alkyl chain substituents formed highly efficient light-harvesting layers on a TiO2 surface. Dye-sensitized solar cells using PcS20 exhibited record efficiency of 6.4% under one-sun irradiation.

We designed and synthesized new substituted carbazole dyes, MK-14 -16, for dye-sensitized solar cells (DSSCs) employing the I−/I3−redox couple. By addition of a hexyloxyphenyl substituent to previously reported dyes MK-1 -2, electron lifetime open circuit voltage DSSCs these were increased, showing comparable values with those using conventional Ru complex dye. This result was achieved by retardation charge recombination, caused more effective blocking I3− ion in electrolyte than that cases...

The photostability of five sensitizer dyes with and without an oligothiophene moiety was studied by means spectroscopic techniques to determine the dyes' suitability for dye-sensitized solar cells. We examined effect light irradiation on adsorbed nanocrystalline TiO2 films under ambient conditions found that containing showed high stability. results transient absorption measurements suggest location holes moieties responsible this observed

Electron lifetime and diffusion coefficient measurements in highly efficient porphyrin-sensitised TiO(2) solar cells showed reduced electron lifetime, consequently, lower photo-induced density under illumination compared to commonly used ruthenium dye (N719)-sensitised cells, which is proposed be the origin of generally open circuit voltage.

Nanoporous-walled tungsten oxide (WO(3)) nanotubes (NTs), which had a more positive conduction band edge level compared to that of TiO(2), were applied various organic dyes for dye-sensitized solar cells (DSSCs). The WO(3) NTs displayed photosensitization the whose lowest unoccupied molecular orbital (LUMO) was relatively conventional TiO(2) electrode and, thus, not applicable electron injection electrode. Electron transport time and lifetime in DSSCs investigated. In comparison based on...

Abstract A series of zinc–phthalocyanine sensitizers ( PcS16 – 18 ) with different adsorption sites have been designed and synthesized in order to investigate the dependence adsorption‐site structures on solar‐cell performances based dye‐sensitized solar cells. The change site affected electron injection efficiency from photoexcited dye into nanocrystalline TiO 2 semiconductor, as monitored by picosecond time‐resolved fluorescence spectroscopy. sensitizer PcS18 , possessing one carboxylic...

Aggregation of adsorbed dye molecules on TiO2 electrode typically decreases the yield photoinduced charge separation at dye/TiO2 interface. The decreased could be caused by alternations energy levels and/or adsorption geometry sensitizers aggregation. We investigated origin for aggregated employing zinc phthalocyanine-sensitized in redox-containing electrolytes. degree aggregation was controlled amount coadsorbent, addition bulky molecular unit to phthalocyanine cores, and alternation angle...

Porous TiO₂electrodes were prepared by oxidizing Ti₃C₂nanosheets at different temperatures in air and tested dye-sensitized solar cells.

When an alkyl-functionalized metal-free organic dye (MK-2) was employed as a sensitizer, dye-sensitized TiO2 solar cells (DSSCs) fabricated with ionic liquid (IL) electrolyte showed energy conversion efficiency of 7.6%, which comparable to that volatile electrolyte. This contrasts the case DSSCs employing conventional Ru complex sensitizer (N719), whose decreased markedly when replaced from IL. As result, IL electrolyte, MK-2 higher than N719. The result mainly attributed longer electron...

A triphenylamine (TPA) dye with two hexyl groups at the opposable 3,3′-positions of a bithiophene linker (1a) was prepared and compared to regio regular 4,3′-dihexylbithiophene unit (1b). The absorption spectrum 1a showed blue shift in comparison 1b, suggesting structure twisted 1b. agreed optimized by DFT calculations. By replacing one thiophene 1b pyridine ring (2a 2b, respectively), further observed. Dye-sensitized solar cells (DSSCs) were from these dyes conventional Ru (N719). Under sun...

In organic photovoltaics (OPVs) using nonfullerene acceptors, the fine-tuning of interfaces between donor and acceptor in bulk-heterojunction (BHJ) structure has become an important factor to improve performance. A series electron-accepting π-conjugated compounds based on benzothiadiazole arenedicarboximides were systematically synthesized investigate impact structural modification molecular orientation at donor–acceptor interfaces. X-ray diffraction surface free energy measurements these...

We performed a detailed and quantitative spectroscopic study of the electron injection dynamics for porphyrin as one organic dyes at an adequate level to discuss dye-sensitized solar cell performance. The kinetics yield TiO2 electrodes in redox-containing electrolytes were measured by femtosecond transient absorption picosecond fluorescence spectroscopy. By comparing two most studied porphyrins with those Ru complex (N719), we have directly elucidated that short-circuit current...

The effect of the donor in an organic dye on electron lifetime dye-sensitized solar cells (DSSCs) employing a cobalt redox electrolyte was investigated. We synthesized dyes with moieties carbazole, coumarin, triphenylamine, and N-phenyl-carbazole measured current-voltage characteristics lifetimes DSSCs these dyes. cell triphenylamine produced highest open circuit voltage longest lifetime. On other hand, lowest shortest obtained coumarin dye, suggesting that attracted couples to surface TiO2...