109th CEMS Colloquium

Title

Synthesis of Periodic Mesoporous Organosilicas for Energy and Environmental Applications

Abstract

Periodic mesoporous organosilicas (PMOs), synthesized via surfactant-directed self-assembly of bridged organosilane precursor [(R’O)3Si-R-Si(OR’)3, R: organic group] are promising candidates as catalyst supports, adsorbents, and optical and electrical devices due to the high surface area, well-defined nanoporous structure and highly functional framework structures [1-3]. Here I present the synthesis of PMOs with a variety of organic groups and their applications to heterogeneous molecular catalysis for solar energy conversion and sustainable organic synthesis, and to organic solar cells. We found unique light-harvesting antenna properties of PMOs [4] and constructed heterogeneous molecular photocatalysis systems for CO2 reduction [5]. We succeeded in synthesis of a novel PMO containing 2,2’-bipyridine ligands within the framework (BPy-PMO) [6]. BPy-PMO showed excellent solid ligand properties for heterogeneous metal complex catalysis, resulting in superior activity, durability, and recyclability to the homogeneous analogous catalysts [7]. We also synthesized hole-transporting PMO films and demonstrated that the PMO film functions as a p-type layer for organic solar cells by filling an n-type PCBM into the mesopores [8]. These results demonstrate the great potential of PMOs as a useful integration platform for construction of efficient molecular-based catalysts and optical devices.

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