TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The second electrode comprises a highly conductive layer comprising silver that may distribute charge over the whole surface.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (disclosed): Compound (I) is prepared by reacting a thio derivative of formula (III) with an alcohol of formula (IV) and pyridine derivative of formula (V) to obtain a thio derivative of formula (VI); reacting a thio derivative of formula (VII) with chlorotrimethylstannane and lithium diisopropylamide to obtain a thio derivative of formula (VIII), and reacting (VI) and (VIII) to obtain (I). Compound (II) is prepared by subjecting (I) to thermal cleavage at 210 degrees C. Preferred Component: The thermally-cleavable group is an alkyl group of an ester.    TECHNOLOGY FOCUS - POLYMERS - Preferred Component: The hole conducting polymer is a polythiophene derivative. Preferred Method: The bulk heterojunction layer is provided on the metal oxide layer by coating a solution of the metal oxide nanoparticles and hole conducting polymer on the metal oxide layer followed by removal of the solvent. The heating of bulk heterojunction layer is done using a laser having a wavelength of 475-532 nm. The metal oxide layer and the bulk heterojunction layer are screen printed as solutions in a thermocleavable solvent. SPECIFIC COMPOUNDS - Compound (2,5,9-trimethyldecan-2-yl)-2,5-dibromothiophene-3-carboxylate (Ia); 2,3-diphenyl-5,7-bis (5-(trimethylstannyl)thiophene-2-yl)thieno(3,4-b)pyrazine; poly-((3'-(2,5,9-trimethyldecan-2-yl)-oxy-carbonyl)-(2,2';5',2'')terthiophene-1,5''-diyl)-co-(2,3-diphenylthieno(3,4-b)pyrazine-5,7-diyl)) are disclosed.    EXAMPLE - 2,5-Dibromothiophene-3-carboxylic acid (10 g) and 2-chloro-3,5-dinitropyridine (7.8 g) was dissolved in dry pyridine in the presence of argon, heated at approximately 40 degrees C for 30 minutes, added with 2,5,9-trimethyl-decan-2-ol (7.7 g), stirred at 120 degrees C for overnight, and cooled to ambient temperature. The obtained mixture was poured into a mixture of water (300 ml), light petroleum (300 ml) and sodium bicarbonate aqueous solution (100 ml) to form an aqueous phase. The obtained aqueous solution was extracted with light petroleum (100 ml) for 3 times, and the combined organic phases were dried over magnesium sulfate and evaporated to obtain (Ia).