Facile infiltration of semiconducting polymer into mesoporous electrodes for hybrid solar cells

Abstract

Hybrid composites of semiconducting polymers and metal oxides are promising combinations for solar cells. However, forming a well-controlled nanostructure with bicontinuous interpenetrating networks throughout the photoactive film is difficult to achieve. Pre-structured ''mesoporous'' metal oxide electrodes can act as a well-defined template for latter polymer infiltration. However, the long range infiltration of polymer chains into contorted porous channels has appeared to elude the scientific community, limiting the advancement of this technology. Here we present a structural and electronic characterisation of poly(3-hexylthiophene) (P3HT) infiltrated into mesoporous dye-sensitized TiO 2 . Through a combination of techniques we achieve uniform pore filling of P3HT up to depths of over 4 mm, but the volumetric fraction of the pores filled with polymer is less than 24%. Despite this low pore-filling, exceptionally efficient charge collection is demonstrated, illustrating that pore filling is not the critical issue for mesoporous hybrid solar cells.

Influence of Ion Induced Local Coulomb Field and Polarity on Charge Generation and Efficiency in Poly(3‐Hexylthiophene)‐Based Solid‐State Dye‐Sensitized Solar Cells

“…The D102 dye, depending on the packing confi guration upon the TiO 2 surface, presents two main optical transitions under photoexcitation, one with a strong intramolecular CT characteristic due to the presence of a donor (indoline unit) and acceptor (rodhanine unit) group in the same molecule [ 15 ] and one with an intermolecular character favored by aggregate confi guration (J-aggregate). [ 16 ] Though we cannot completely exclude the presence of dye aggregates, the absorption spectrum from the TiO 2 dye with D102 molecule showed in Figure 1 b does not present any evident feature from J-aggregates species, [ 17 ] therefore we assume that the intramolecular CT state is the dominant species under photo-excitation in these samples.…”

Pore Filling of Spiro‐OMeTAD in Solid‐State Dye‐Sensitized Solar Cells Determined Via Optical Reflectometry

“…It relies only on the assumption that the pore-filling is uniform from top to bottom, which is well supported by previous literature and cross-sectional SEM. 13,14,39 However, beyond measuring the pore-filling of manufactured films, it would be useful to have a predictive tool which to estimate the pore-filling for given coating Figure 4. Hence, as described elsewhere, the pore-filling fraction (PF) can be written as 13…”

Nanoscale investigation on large crystallites in TiO2 nanotube arrays and implications for high-quality hybrid photodiodes

“…For our preliminary experiments, however, we focused on the well-known standard material Z907 since its properties have been extensively described in the literature [29]. Besides, for the sake of simplicity, we did not subject the nanotubes to an additional TiCl 4 treatment or use any additives like 4-tert-butylpyridine or lithium salts, all of which are known to have positive effects on the cell's V OC and especially I SC [30,31].…”