Preparation and structure of a new layered organic–inorganic hybrid between the protonated form of a perovskite Bi2SrTa2O9 and tetraphenylporphyrin by the intercalation behavior

The intercalation of n-alkylamines (including propylamine, octylamine, dodecylamine and octadecylamine) and tetraphenylporphyrin (TPP) into H1.8[Sr0.8Bi0.2Ta2O7](HST), the protonated form of a layered perovskite Bi2SrTa2O9, as well as their arrangements in the interlayer of H1.8[Sr0.8Bi0.2Ta2O7] have been investigated. Relationship between the interlayer distances and the lengths of n-alkyl chains reveals that n-alkylamines are arrayed in the interlayer space of HST with bilayer arrangements (propylamine with a titled angle of 60° to the perovskite-like slabs, while the others vertical to the slabs); TPP with a trilayer arrangement to the surface of perovskite-like slabs. Reaction time for intercalation of n-alkylamines has been shortened from 7 days to 1 day by utilizing chromatography instead of refluxing. The interlayer distance of HST was enlarged gradually from the shortest n-alkyl chain, propylamine to the longest n-alkyl chain, octadecylamine and was expanded to the largest with the intercalation of TPP. The analysis of IR spectra shows that perovskite-like slabs of Bi2SrTa2O9 were retained in the entire process of intercalation reactions and a clear blue-shift could be observed from Bi2SrTa2O9 to its protonated form HST in UV–vis absorption spectra.