This Perspective reviews recent advances in cage-like silsesquioxanes-based hybrid materials, ranging from monomer functionalization and materials preparation to application.

A multifunctional hybrid porous material with a S _BET of 1910 cm ² g ⁻¹ was prepared by the Friedel–Crafts reaction of octavinylsilsesquioxane (OVS) with tetraphenylethene (TPE). It exhibits highly selective adsorption for dye molecules and fluorescence detection for metal ions. A moderate CO ₂ adsorption capacity of 1.42 mmol g ⁻¹ at 273.0 K/101 kPa is also found for this material.

A novel hybrid nanoporous network was easily fabricated by the one-step Heck reaction of octavinylsilsesquioxane with dibromothiophene. FTIR, solid state CP-MAS-NMR (¹³C and ²⁹Si), and elemental analysis indicate that a thiophene unit has been successfully introduced into the silsesquioxane-based network. The Brunauer–Emmett–Teller (BET) measurement shows that this hybrid network possesses a high surface area of 915 m² g⁻¹, a large pore volume of 1.61 cm³ g⁻¹, and unique hierarchical pores, i.e. uniform micropores and continuous multimodal mesopores. Remarkably, it displays an ultrahigh adsorption capability of 1402 mg g⁻¹ for Rhodamine B, and 862 mg g⁻¹ for Methylene Blue, which are among the highest values compared with other reported adsorbents. It also shows a good removal capability of toxic heavy metal ions from wastewater. More importantly, it could remove multiple pollutants efficiently from wastewater by simple filtration and possesses excellent regeneration performance.

Friedel–Crafts reaction of cubic octavinylsilsesquioxane (OVS) and benzene results in a series of hybrid porous polymers (HPPs). The resulting materials, HPP-1 to HPP-4, show relatively high porosity with apparent Brunauer–Emmett–Teller surface areas in a range of 400 m² g⁻¹ to 904 m² g⁻¹, with total pore volumes in the range of 0.24 cm³ g⁻¹ to 0.99 cm³ g⁻¹. Their porosities can be fine tuned by adjusting the mole ratios of OVS and benzene. They feature both micro- and mesopores (HPP-1 and HPP-2) to almost mesopores (HPP-3 and HPP-4) in the networks. The ratios of micropore volume to total pore volume for HPP-1 to HPP-4 were 0.58, 0.42, 0.10, and 0.11, respectively. These materials exhibit comparable surface area and high thermal stability in a N₂ atmosphere. The gas sorption applications reveal that HPP-3 possesses a H₂ uptake of 3.47 mmol g⁻¹ (0.70 wt%) at 77 K and 760 mmHg and a CO₂ uptake of 0.62 mmol g⁻¹ (2.73 wt%) at 298 K and 760 mmHg. These results indicate these materials are promising candidates for storing H₂ and CO₂. In addition, HPP-4 has been successfully postfunctionalized with 3-mercaptopropionic acid via thiol–ene “click” reaction.