Fabrication, Optical Modeling, and Color Characterization of Semitransparent Bulk‐Heterojunction Organic Solar Cells in an Inverted Structure

Abstract

Semitransparent inverted organic photodiodes are fabricated with a Baytron PH500 ethylene‐glycol layer/silver grid as the top electrode. Reasonable performances are obtained under both rear‐ and front‐side illumination and efficiencies up to 2% are achieved. Some light is shed on visual prospects through optical simulations for a semitransparent device of poly(3‐hexylthiophene) (P3HT) and the C60 derivative 1‐(3‐methoxycarbonyl)propyl‐1‐phenyl[6,6]C71 (PC70BM) in the inverted structure. These calculations allow the maximum efficiency achievable to be predicted for semitransparent cells based on P3HT:PC70BM versus the transparency perception for a human eye. The simulations suggest that low‐bandgap materials such as poly[2,6‐(4,4‐bis‐(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene)‐alt‐4,7‐(2,1,3‐benzothiadiazole)] (PCPDTBT) have a better potential for semitransparent devices. In addition, the color range recognized by the human eye is predicted by the optical simulation for some semitransparent devices including different active layers.

Facile preparation of TiOXfilm as an interface material for efficient inverted polymer solar cells

“…As we know, TiO X lms are suitable electron transport layers in organic solar cells. 21,23 However, high quality and feasible solution-processed TiO X nanolms applied via coating or roll-to-roll processing still need to be developed. Tetrabutyl titanate (TBT) is widely employed as the Ti precursor to obtain TiO X by the traditional sol-gel method.…”

“…), and the ITO coated glass as the cathode is modied using stable n-type metal oxides such as titanium oxide (TiO X ), [18][19][20][21][22][23][24][25] zinc oxide (ZnO), [26][27][28] and cesium carbonate (Cs 2 CO 3 ).…”

Photochemical upconversion: present status and prospects for its application to solar energy conversion

“…Bifacial -or semitransparent, as is often used synonymously -organic solar cells are not trivially made as the standard layer sequence requires a low work function metal as back contact which cannot easily be replaced by a transparent electrode. Inverted device architectures have recently enabled the fabrication of semitransparent polymer-based solar cells, mostly with PEDOT:PSS transparent conductive polymer front contacts 117,118 or a combination of metal oxides and a very thin semitransparent metal. 119 In our study we employed semitransparent solar cells following the second approach, fabricated at Karlsruhe Institute of Technology (KIT).…”

Semi-transparent polymer solar cells

“…This electrode must be deposited when the absorber layer has already been deposited on the substrate and a nonaggressive deposition procedure needs to be used. Several different options have been considered, such as low-temperature annealed indium tin oxide (ITO), [42][43][44][45][46][47][48] a three-layer architecture combining a dielectric layer, an ultra thin metal layer, and a second dielectric layer, [49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64] PEDOT, [65][66][67] silver grid, 68 graphene, [69][70][71] carbon nanotubes, 67,72 and silver nanowires (AgNW). [73][74][75][76][77][78] However, the need for a nondestructive deposition technique for the top semi-transparent electrode is probably not the major issue that semi-transparent OPV cells must overcome before becoming an industrially viable solution.…”