Photochemistry catalyzed by copolymer-templated mesoporous SiO2: Decomposition of methanol and formic acid.
Photochemical reactions of methanol and formic acid on L64 copolymer-templated mesoporous SiO2 have been investigated by Fourier transform infrared spectroscopy. Although SiO2 has been generally recognized to be photochemically inert, the reaction pathways HCOOH(a), HCOO(a)/SiO2 --> CO(2(g)) and CH3OH(a), CH3O(a)/SiO2 --> CH2O(a) --> HCOO(a) --> CO(2(g)) are demonstrated. The photons used in this study are unable to promote the SiO2 valance band electrons to the conduction band. Therefore photoholes take no part in these reactions. Mechanisms involving charge transfer and the surface species possible to initiate the photooxidation on mesoporous SiO2 under irradiation are discussed. For comparison purposes, parallel studies are also conducted for nonporous SiO2 to show the effect of porosity of SiO2 on the reactivity.
Lin
Yi-Shiue
YS
Department of Chemistry, National Cheng Kung University, 1, Ta Hsueh Road, Tainan, Taiwan, Republic of China.
Chen
Meng-Tso
MT
Lin
Yu-Feng
YF
Pang
Yi-Shung
YS
Lin
Hong-Ping
HP
Lin
Jong-Liang
JL