A Mesoporous Lead-Doped Titanium Oxide Compound with High Performance and Recyclability in I₂ Uptake and...

A three-dimensional (3D) mesoporous material with an atomically precise structure, Ti₁₆Pb₅O₁₆(C₆H₅CO₂)₂(OCH₃)₄₀ (TiPb), comprised of a novel high-nuclearity Pb-doped titanium oxide cluster (TOC), was synthesized. TiPb exhibited a surface area of 45 m² g^-1 and a pore diameter of 3.5 nm. It exhibited an uptake capacity of I₂ of ≤2.2 g g^-1 in vapor, and the performance was maintained after seven uptake-release cycles. TiPb also showed a high adsorption ratio and capacity (93% and 3.1 g g^-1) in hexane. The characterization data, including Fourier transform infrared, Raman, and powder X-ray diffraction, suggested the lattice structure of TiPb was rigid and I₂ was accommodated in the pores of TiPb. To the best of our knowledge, this is the first example of using a TOC in I₂ adsorption. In addition, TiPb showed excellent activity and recyclability in visible-light degradation of dye pollutants and photocurrent generation. Our structural analysis suggested the alkoxide ligands within the channels of TiPb build up a confined polar environment and thereby facilitate I₂ accommodation, and meanwhile, the improved performances and stabilities of TiPb are correlated with its cluster-based, 3D hierarchical structure.