Urchin-Inspired TiO2@MIL-101 Double-Shell Hollow Particles: Adsorption and Highly Efficient Photocatalytic Degradation of Hydrogen Sulfide

Titanium dioxide (TiO2) is a commonly used photocatalysis for the oxidation of hydrogen sulfide (H2S). However, the low surface area and adsorption ability of TiO2 limit the photocatalytic decomposition rate. Here, a tunable metal–organic framework (MOF) coating is applied to hollow TiO2 nanoparticles using a versatile step-by-step self-assembly strategy. The hollow structure provides a high surface area, and the selected MIL-101 (Cr) MOF has a high and regenerable adsorption ability for H2S. The TiO2@MIL-101 double-shell hollow particles enable a catalytic cycle involving simultaneous adsorption and degradation of H2S, with considerably enhanced photocatalytic reaction rate. This work provides a method for improving photocatalytic performance through the design of hollow MOF-based materials that rationally combine the power of MOF and TiO2.