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Bulk heterojunction (BHJ) solar cells have made great progress over the past decade and consequently are now attracting extensive academic and commercial interest because of their potential advantages: lightweight, flexible, low cost, and high-throughput production. Polymer conductivity is a key factor for improving the performance of electronic and photonic devices. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is promising for use as a next-generation transparent electrode of optoelectronic devices. In this research, we compare the effect of nanomorphology on conductivity, and power conversion efficiency of polymer organic solar cells prepared by the spin-and spray-coating methods.To improve the conductivity of spray-deposited PEDOT:PSS, we modified the PEDOT:PSS films by simple UV irradiation and by UV irradiation with treatment using various solvents such as methanol, ethanol, acetone, acetonitrile, hydrochloric acid, and sulfuric acid to form a hole transport layer (HTL). The active layer of PTB7:PC 70 BM is spray-coated on top of the PEDOT:PSS layer. The films were examined by optical spectroscopy, micro-Raman spectroscopy, and conductivity measurements. The surface morphology of the deposited films was examined by atomic force microscopy (AFM). The current density-voltage (J-V) characteristics were measured under illumination with simulated solar light at 100 mW/cm 2 (AM 1.5G) using an oriel 1000 W solar simulator. The obtained results are expected to have a considerable impact and suggest a bright future for organic polymer solar cells.

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A convenient method has been developed for the conversion of indoles into isatin derivatives in good to excellent yields. The general process utilizes our efficient one-pot method for bromination and oxidation with an N-bromosuccinimide -dimethyl sulfoxide reagent. 1-Alkyl-7-azaindoles are readily available in excellent yields from the reaction of the sodium salt of 7-azaindole with appropriate alkyl halides in dimethylacetamide. Similar reactions with 1-alkyl-5-cyanoindoles and indole gave 1-alkyl-5-cyanoisatins and isatin, respectively.

A b s t r a c t -Irradiation o f 1-alkylisatins ( 1 ) in degassed alcohols afforded 1 -alkyl-3-hydroxyoxindoles ( 2 ) and 1-alkyloxindoles ( 3 ) as chemoselective photoproducts. The photochemical behavior of carbonyl groups of cyclic vicinal polyketones has received considerable attention in the last few years.' On the other hand, the photochemical reactions of heterocyclic vicinal diketones have also attracted interest from synthetic viewpoints.'Recently, it has been reported that photochemical reaction of