Publications by authors named "O Lozman"

Organic photovoltaics are a sustainable and cost-effective power-generation technology that may aid the move to zero-emission buildings, carbon neutral cities, and electric vehicles. While state-of-the-art organic photovoltaic devices can be encapsulated to withstand air and moisture, they are currently still susceptible to light-induced degradation, leading to a decline in the long-term efficiency of the devices. In this study, the role of ultraviolet (UV) radiation on a multilayer organic photovoltaic device is systematically uncovered using spectral filtering.

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with a unique design and semitransparent blue appearance is presented. These modules are implemented in a solar tree installation at the German pavilion in the EXPO2015 in Milan/IT. The modules show power conversion efficiencies of 4.

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The success of semiconducting organic materials has enabled green technologies for electronics, lighting, and photovoltaics. However, when blended together, these materials have also raised novel fundamental questions with respect to electronic, optical, and thermodynamic properties. This is particularly important for organic photovoltaic cells based on the bulk heterojunction.

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Unlabelled: The impact of side-chain variations on the photothermal stability of solar cells containing poly(benzodithiophene-diketopyrrolopyrrole) polymers are investigated in the absence of oxygen. Four different side-chains of benzodithiophene (BDT) are synthesized and copolymerized with diketopyrrolopyrrole (DPP) by Stille polymerization. The photothermal stability is measured as active layer blends with phenyl-C61-butyric acid methyl ester (PCBM) in encapsulated inverted photovoltaic cell architecture with zinc oxide and

Pedot: PSS as transport layers (ITO/ZnO/active layer/

Pedot: PSS/Ag).

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The solution and liquid crystalline phases formed by dissolution of the dye Edicol Sunset Yellow (ESY) in water have been examined using optical microscopy, multinuclear NMR (1H, 2H, 13C, 23Na), and X-ray diffraction. From the solution 1H and 13C spectra (particularly 13C), it is clear that the tautomeric form present in all these phases is the hydrazone, NH, structure, not the usually given azo, OH, form. Two chromonic mesophases occur: a nematic (N) phase at approximately 30-40 wt % and a hexagonal (M) phase at approximately 40-45 wt %.

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