Selective dye adsorption and metal ion detection using multifunctional silsesquioxane-based tetraphenylethene-linked nanoporous polymers
Multifunctional hybrid fluorescent porous materials have been prepared by the Friedel–Crafts reaction of octavinylsilsesquioxane (OVS) with tetraphenylethene (TPE). These hybrid porous polymers possess high surface areas of up to 1910 cm2 g−1, and bimodal pore structures with micropores centered at ≈1.4 nm and mesopores centered at ≈4.5 nm. They show a moderate CO2 adsorption capacity of 6.25 wt% (1.42 mmol g−1) at 273 K/101 kPa. Remarkably, they exhibit highly size-selective adsorption of dye of 1666 mg g−1 for rhodamine B (RB), 1040 mg g−1 for congo red (CR) and 862 mg g−1 for crystal violet (CV). Furthermore, the incorporation of a tetraphenylethene unit induces higher fluorescence (λem = 490 nm) and high sensitivity for Fe3+, Cu2+ and Ru3+, especially for Fe3+ with KSV = 140 K M−1. They are very promising for multiple applications in dye separation, sensors, etc.