Langmuir–Blodgett Films of Porphyrins for Applications in Photovoltaics

Abstract

AbstractThe use of organic materials in the realization of devices for the conversion of solar energy is a hot topic in chemistry, physics, and material science since many years. While the attention is strongly paid toward the synthesis and engineering of new molecules with adequate chemical and physical properties, such materials have to be transferred onto solid substrates, in order to construct functioning devices with high reproducibility and optimizing the performances. Then, deposition technique plays a paramount role in the realization of a photovoltaic device. Moreover, photoactive thin films are often carried out by multilayer stacks with a high spatial organization, and this observation prompted out many researchers to use layer-by-layer, Langmuir–Blodgett (LB), or Langmuir–Schaefer (LS) methods as deposition techniques for the fabrication of such devices. One of the most used class of substances for depositing LB or LS thin films is represented by the porphyrin derivatives whose filmability features can be improved by means of chemical functionalization or by the co-spreading of filmmaker molecules such as octadecylamine or arachidic acid. Furthermore, porphyrins show a very high light harvesting, and they are well-known electron donors, as it happens in the photosynthesis process. In this chapter, several examples of LB and LS film of porphyrin derivatives both used for the realization of photovoltaic devices and for studying the charge transfer processes have been reported.KeywordsFullerenesLangmuir–Blodgett filmsLangmuir–Schaefer filmsPhotovoltaicsPorphyrins