Synthesis of chromophores with porphyrin core and triphenylamine branching effect on the properties of linear/two-photon absorption

The synthesis of a serial new triphenylamine-multibranching chromophores with porphyrins “core” were reported and UV–vis absorption, one/two-photon fluorescence and two-photon absorption (TPA) cross-section were investigated. The triphenylamine-branching effect on their properties, including the different branches numbers and different generational multibranches were investigated in detail. The results show the different branches numbers and the different generational multibranches had a remarkable effect on the absorption and one/two-photon fluorescence properties of these chromophores. The two-photon absorption cross-section value (σs) of the higher generational multibranched triphenylamine chromophore TPP-(G2X)3 is 1058.25 GM, which is three times bigger than the others. Comparatively, the higher generational multibranched triphenylamine effect shows more significant contribution to two-photon absorption enhancement and obviously improves two-photon absorption cross-section behavior. This is greatly valuable for designing and synthesizing novel TPA materials.

► The different triphenylamine-branches numbers and the different generational multibranches had a remarkable effect on the absorption and one/two-photon fluorescence properties.
► The fluorescence relative intensity (area) ratio of the triphenylamine “branch” and porphrin “core” in chromophore TPP(G2X)3 are almost 2:1 for 800 nm excited TPA fluorescence emission and 10:1 for one-photon fluorescence emission, respectively.
► The higher generational multibranched triphenylamine effect shows more significant contribution to two-photon absorption enhancement and obviously improves two-photon absorption cross-section behavior.