title: Spatially orthogonal chemical functionalization of a hierarchical pore network for catalytic cascade reactions.
abstract: The chemical functionality within porous architectures dictates their performance as heterogeneous catalysts; however, synthetic routes to control the spatial distribution of individual functions within porous solids are limited. Here we report the fabrication of spatially orthogonal bifunctional porous catalysts, through the stepwise template removal and chemical functionalization of an interconnected silica framework. Selective removal of polystyrene nanosphere templates from a lyotropic liquid crystal-templated silica sol-gel matrix, followed by extraction of the liquid crystal template, affords a hierarchical macroporous-mesoporous architecture. Decoupling of the individual template extractions allows independent functionalization of macropore and mesopore networks on the basis of chemical and/or size specificity. Spatial compartmentalization of, and directed molecular transport between, chemical functionalities affords control over the reaction sequence in catalytic cascades; herein illustrated by the Pd/Pt-catalysed oxidation of cinnamyl alcohol to cinnamic acid. We anticipate that our methodology will prompt further design of multifunctional materials comprising spatially compartmentalized functions.
authors.affiliation: European Bioenergy Research Institute, Aston University, Birmingham B4 7ET, UK.
authors.forename: Christopher M A
authors.identifier: http://orcid.org/0000-0002-3651-7314
authors.initials: CM
authors.lastname: Parlett
authors.affiliation: European Bioenergy Research Institute, Aston University, Birmingham B4 7ET, UK.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Isaacs
authors.affiliation: Department of Chemistry, University of Durham, Durham DH1 3LE, UK.
authors.forename: Simon K
authors.initials: SK
authors.lastname: Beaumont
authors.affiliation: Department of Chemistry, University of Durham, Durham DH1 3LE, UK.
authors.forename: Laura M
authors.initials: LM
authors.lastname: Bingham
authors.affiliation: Institute for Materials Research, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Nicole S
authors.initials: NS
authors.lastname: Hondow
authors.affiliation: European Bioenergy Research Institute, Aston University, Birmingham B4 7ET, UK.
authors.forename: Karen
authors.identifier: http://orcid.org/0000-0003-4873-708X
authors.initials: K
authors.lastname: Wilson
authors.affiliation: European Bioenergy Research Institute, Aston University, Birmingham B4 7ET, UK.
authors.forename: Adam F
authors.identifier: http://orcid.org/0000-0002-2153-1391
authors.initials: AF
authors.lastname: Lee
mesh_terms: D002384:Catalysis; D003102:Colloids; D008422:Materials Testing / Q000379:methods*; D046529:Microscopy, Electron, Transmission; D010165:Palladium; D010984:Platinum; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D003102:Colloids; C509969:SBA-15; D010984:Platinum; D010165:Palladium; D012822:Silicon Dioxide