Abstract
Several remarkable organic-inorganic multilayer hybrids, which include extremely high-density photosensitizer dyes, without aggregation have been produced using a method based on "size-matching intercalation" with a simple immersion technique. This study focuses on the intercalation process. Temporal progress of the intercalation of the +4-charged cationic porphyrin molecules in the interlayers of the anionic synthetic clay particles, which were fabricated into a thin transparent film, was observed by a spectroscopic method at various temperatures. The distance between the adjacent cations in the cationic porphyrin molecule was designed to be close to the average distance between the clay anionic sites, which is called the size-matching condition. When the loading amount of the porphyrin corresponded to 30% versus the cation exchange capacity (CEC) of the clay in a film, almost all the porphyrin molecules were intercalated into the clay film during a 10 h immersion. No aggregated species were observed at any time during the immersion. After the immersion, the average occupied area of one porphyrin molecule was estimated to be 8.3 nm^2. The time course of the intercalation was well simulated by a simple exponential function with a single time rate constant for each temperature condition. The Arrhenius plot of the rate was linear, and the Arrhenius activation energy estimated from the rate constants was 26.8 kJ mol^<-1>.
