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Solar Cells. (solar + cells)

Distribution by Scientific Domains
Physics and Astronomy75%

Selected Abstracts

Perylene,Oligothiophene,Perylene Triads for Photovoltaic Applications

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 17 2005
Jens Cremer
Abstract A series of novel acceptor,donor,acceptor triad systems, consisting of head-to-tail-coupled oligo(3-hexylthiophene)s integrated between two terminal perylenemonoimides are described. These hybrid molecules, which differ by the length of the oligothiophene units from a quaterthiophene up to a dodecithiophene were synthesized by an effective palladium-catalyzed Ullmann-type homo-coupling reaction in good yields. The optical and electrochemical properties of these compounds were determined, and on the basis of this series structure-property relationships have been established which provide vital information for the fabrication of the corresponding photovoltaic devices. Because the synthesized perylenyl-oligothiophenes distinguish themselves by a high absorption between 300 and 550 nm and an almost complete fluorescence quenching of the perylene acceptor, they meet the requirements for organic solar cells. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]

Correlation of pre-breakdown sites and bulk defects in multicrystalline silicon solar cells

PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 2-3 2009
Dominik Lausch
Abstract Strong correlation between the pre-breakdown sites visible in dark lock-in thermography due to local heating and the intensity of spatially resolved electroluminescence of reverse-biased solar cells was observed. By comparing differently texturised solar cells we could show that the pre-breakdown sites are not correlated to the surface morphology, e.g. etch pits resulting in local field enhancement. The positions of the pre-breakdown sites are identical for acidic and alkaline texturised solar cells and therefore are directly related to bulk defects in the wafer. Nevertheless, the breakdown voltage is lower for acidic texturised solar cells; the parameters of breakdown are influenced by the texture in contrast to the position. Also pre-breakdown sites are observed in areas without specific surface features for alkaline texturised solar cells. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Optical, electrical and structural characterization of CuInSe2 thin films

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 9 2005
C. Calderón
Abstract Structural, optical and electrical properties of polycrystalline p-type CuInSe2 (CIS) thin films, grown by a process including a chemical reaction between Cu and InxSey thin films deposited sequentially by evaporation, followed by annealing in a Se environment, were studied through XRD (X-ray diffraction), transmittance and Hall voltage measurements. The conditions to grow CIS thin films in the , phase of the chalcopyrite structure were found through a parameter study. CIS films with these characteristics are usually used for the fabrication of high efficiency solar cells. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Photoluminescence and time-resolved photoluminescence in Cu(In,Ga)Se2 thin films and solar cells

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 5 2009
Sho Shirakata
Abstract Photoluminescence (PL) and time-resolved PL (TR-PL) studies have been carried out on Cu(In,Ga)Se2 (CIGS) thin films and solar cells (ZnO/CdS/CIGS) to study the recombination of the photo-excited carriers. The CIGS solar cells exhibited intense near-band-edge (NBE) PL compared with the CIGS films by two orders of magnitude. PL decay time of the cell is strongly dependent on the repetition frequency of the excitation light. PL decay time of the cell is longer than that of the corresponding CIGS thin film. The chemical bath deposition of the CdS buffer layer on CIGS leads to changes in PL intensity, defect-related PL and the PL decay time. They are discussed with relation to the substitution of Cd atom at the Cu site at the Cu-deficient surface of CIGS thin film. Under the open circuit condition, NBE-PL is stronger and the decay time is longer compared with those under the short circuit condition. PL of the cell under the load was examined, and PL intensity and PL decay time are related to the photovoltage during PL measurements. Low temperature PL suggests that the Cd diffusion during the CBD process is pronounced for low Ga content CIGS. The authors demonstrate the effectiveness of PL as a powerful non-destructive device and photovoltaic characterization methods of CIGS solar cells. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]