Silsesquioxane-based fluorescent nanoporous polymer derived from a novel AIE chromophore for concurrent detection and adsorption of Ru3+

Abstract

2-(2,6-bis((E)-4-(diphenylamino)styryl)-1-methylpyridin-4(1 H)-ylidene)malononitrile (TPA-TCMP) offering aggregation-induced emission(AIE) with practical fluorescence efficiency was easily transformed from 2-(2,6-bis(4-(diphenylamino)stryryl-4H-pyranylidene)malononitrile (TPA-DCM) which suffers from aggregation-caused quenching (ACQ) by replacing oxygen atom with methylamine group. Subsequently, a hybrid fluorescent nanoporous material (THPP) was prepared by Friedel-Crafts reaction of TPA-TCMP with octavinylsilsesquioxane, [vinylSiO1.5]8 (OVS). THPP possesses a good porosity with a high surface area of 620 m2 g−1, a large pore volume of 0.54 cm3 g−1. It also displays a high thermal stability with 5 % mass loss thermal decomposition temperature above 400 °C in N2 atmosphere and a good pH stability ranging from 4–9. More importantly, it offers a large Stokes shift of 180 nm. The adsorption of Ru3+ on THPP dramatically quenches the fluorescence emission allowing the efficient detection of Ru3+with high selectivity, and the detection limit (LOD) is calculated to be 5.2 × 10−6 mol L−1. Moreover, THPP can adsorb Ru3+ with an equilibrium adsorption capacity of 208 mg g−1.