Enhanced Photocatalysis of Rhenium(I) Complex by Light-Harvesting Periodic Mesoporous Organosilica

Abstract

This paper describes a new conceptual design for enhancement of photocatalytic CO(2) reduction of a rhenium(I) complex by light harvesting of periodic mesoporous organosilica (PMO). Mesoporous biphenyl-silica (Bp-PMO) anchoring fac-[Re(I)(bpy)(CO)(3)(PPh(3))](+)(OTf)(-) (bpy =2,2'-bipyridine; OTf = CF(3)SO(3)) in the mesochannels was synthesized by co-condensation of two organosilane precursors, 4,4'-bis(triethoxysilyl)biphenyl and 4-[4-{3-(trimethoxysilyl)propylsulfanyl}butyl]-4'-methyl-2,2'-bipyridine in the presence of a template surfactant, followed by coordination of a rhenium precursor, [Re(I)(CO)(5)(PPh(3))](+)(OTf)(-) to the bipyridine ligand in the mesochannels. The 280 nm light was effectively absorbed by the biphenyl groups in Bp-PMO, and the excited energy was funneled into the Re complex by resonance energy transfer, which enhanced photocatalytic CO evolution from CO(2) by a factor of 4.4 compared with direct excitation of the Re complex. Bp-PMO had an additional merit to protect the Re complex against a decomposition by UV irradiation. These results demonstrate the potential of PMOs as a light-harvesting antenna for designing various photoreaction systems, mimicking the natural photosynthesis.

Temperature dependent NIR emitting lanthanide-PMO/silica hybrid materials

“…[11][12][13][14][15][16][17] Other suitable sensitizer ligands as bipyridine, acridone, mercaptobenzoic acid or 2-phenoyltrifluoroacetonate have been successfully incorporated as bridging organic compounds into PMO framework. [18][19][20][21] Recently, we have reported the incorporation of dipyridyl-dihydropyridazine moieties on the surface through hetero Diels-Alder reaction between the double bonds on an ethenylene-bridged PMO and a tetrazine derivative. 5 Tetrazinederived ligands can be employed as sensitizers for Ln 3+ ions and due to their low triplet level they can be well matched with the accepting levels of NIR emitting lanthanides such as Nd 3+ [27][28][29] There are various ways of assessing the temperature or temperature change of a material by employing luminescence features.…”

Highly efficient photochemical HCOOH production from CO2 and water using an inorganic system

“…There have been a lot of attempts to realize similar reactions to natural photosynthesis using mainly organic complexes. Carbon monoxide (CO) [1][2][3][4] and formic acid (HCOOH) 5 have been successfully produced from CO 2 by light illumination. Research interest has recently extended to certain types of hybrid materials, [6][7][8][9] and reactor systems have been been reconsidered in connection with the shape of cataysts.…”

Mesoporous Silica Functionalized by Cyclam–Metal Groups: Spectroscopic Studies and Numerical Modeling

“…magneto-optical switchers and bi-sensors [1][2][3], drug delivery controllers [4][5][6] or catalytic agents [7,8]. Thus, the considered materials are the subject of broad field of investigations [9][10][11][12] since the functionalities can be tuned by changing the nature of the functional groups such as nanoparticles [13], magnetic clusters [14], organic or organometallic molecules [15].…”