Publications by authors named "Evan C Ngo"

In this work role of solvent additive namely 1,8 diiodoctane (DIO) on the nanoscale morphology and its relation with the charge transport of poly(diketopyrrolopyrrole-terthiophene) (PDPP3T):PCBM solar cells has been investigated. Addition of DIO led to enhanced structural ordering as observed from optical measurements. Photovoltaic devices processed with DIO additive showed improved efficiencies due to significant enhancement in short circuit current density.

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Single and double junction solar cells with high open circuit voltage were fabricated using poly{thiophene-2,5-diyl-alt-[5,6-bis(dodecyloxy)benzo[c][1,2,5]thiadiazole]-4,7-diyl} (PBT-T1) blended with fullerene derivatives in different weight ratios. The role of fullerene loading on structural and morphological changes was investigated using atomic force microscopy (AFM) and X-ray diffraction (XRD). The XRD and AFM measurements showed that a higher fullerene mixing ratio led to breaking of inter-chain packing and hence resulted in smaller disordered polymer domains.

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Charge transport and bimolecular recombination dynamics were correlated with nanomorphology in polymer solar cells. The morphology of poly(diketopyrrolopyrrole-terthiophene) (PDPP3T) and phenyl-C61-butyric acid methyl ester (PC60BM) blend films was modified using different solvent additives namely 1-chloronaphthalene (CN), 1,8-diiodooctane (DIO) and 1,8-octanedithiol (ODT) and their role on steady state and transient optoelectronic properties was investigated. The energy filtered transmission electron microscopy (EFTEM) images showed that additives (e.

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