Efficient photoinduced charge separation in layered zirconium viologen phosphonate compounds. [Erratum to document cited in CA120(2):18913f]

Photocurrent Generation in Multilayer Organic−Inorganic Thin Films with Cascade Energy Architectures

“…The photocurrent behavior observed for both electrodes is a significant improvement over that of the earlier reported electrode assembled from films of ZrPV and Zr phenylenediamine bisphosphonate (PAPD) donor films 2a. The porphyrin derivatives offer the advantage of strong absorption in the visible region relative to phenylenediamine (PAPD), which is active in the UV region (250−300 nm).…”

“…Thus, if recombination can be minimized, V oc can be maximized. However, from thermodynamic considerations of the balance between radiation and generation, one finds that recombination cannot be reduced below its radiative component, yielding a basic limit for V oc 2b. Since we consider the photocurrent to be linearly dependent with the light intensity, this behavior is expected for a p−n hetero junction device .…”

“…Mimicking the photosynthetic process is one of the most important goals in modern chemistry. The aim is to construct an artificial system that mimics the overall energy transformation process in natural photosynthesis, in which photoinduced charge separation leads to reduction and oxidation reactions, effectively converting optical energy into chemical potential. − Systematic organization of photon harvesting groups, electron donors, and electron acceptors on the molecular level is the basis of efficient photoinduced charge separation, with minimum back electron transfer. ,− The construction of molecular systems, with redox components arranged at fixed distances by covalent bonding, has been extensively studied. − Charge separation rates of well-designed donor−acceptor pairs in these molecular systems can be very high; however, the charge recombination rate is often very high as well. This results in low charge separation quantum yields and leaves the charge-separated state extremely short-lived (picosecond or less) …”

“…Langmuir− Blodgett and self-assembly ,,, techniques have been successfully used to organize photoactive molecules into highly ordered macroscopic structures. Using self-assembly methods, it was possible to organize molecular redox components in a stable lamellar structure at various solid supports.…”

“…We recently reported photocurrent generation from a photoelectrode made from Zr phosphonate multilayers of phenylenediamine (electron donor) and viologen (electron acceptor) . This device produced a stable and repeatable photocurrent upon irradiation of light in the 250−350 nm region.…”