TY - JOUR
T1 - Surface reaction of 2-propanol on modified Keggin type polyoxometalates
T2 - In situ IR spectroscopic investigation of the surface acid-base properties
AU - Iwanowa, Xenia
AU - Strunk, Jennifer
AU - Löffler, Elke
AU - Muhler, Martin
AU - Merz, Klaus
PY - 2013/6
Y1 - 2013/6
N2 - In order to investigate the influence of modified Keggin-polyoxometalates and supported gold particles on reactivity and reaction pathways in thermal 2-propanol oxidation, titanium-substituted, insoluble Cs+-salts of the Keggin-heteropolytungstate (H3PW12O40) Cs3PW12O40 1, Cs5PW11TiO40·nH2O 2, and supported gold composite Au/Cs5PW11TiO40·nH2O 3 were synthesized and characterized as molecular model catalysts. The Ti-substituted polyoxometalate 2 did not show any observable activity in the gas phase oxidation of 2-propanol. The presence of gold nano-particles activates the supporting polyoxometalate 3 and enhances formation of different oxidation products (acetone, diisopropyl ether) depending on the presence of different types of active sites. The formation of the diisopropyl ether involves two adjacent 2-propanol molecules adsorbed on two different types of active sites, whereas the dehydrogenation reaction for the acetone formation involves the initial adsorption of 2-propanol on one type of active site.
AB - In order to investigate the influence of modified Keggin-polyoxometalates and supported gold particles on reactivity and reaction pathways in thermal 2-propanol oxidation, titanium-substituted, insoluble Cs+-salts of the Keggin-heteropolytungstate (H3PW12O40) Cs3PW12O40 1, Cs5PW11TiO40·nH2O 2, and supported gold composite Au/Cs5PW11TiO40·nH2O 3 were synthesized and characterized as molecular model catalysts. The Ti-substituted polyoxometalate 2 did not show any observable activity in the gas phase oxidation of 2-propanol. The presence of gold nano-particles activates the supporting polyoxometalate 3 and enhances formation of different oxidation products (acetone, diisopropyl ether) depending on the presence of different types of active sites. The formation of the diisopropyl ether involves two adjacent 2-propanol molecules adsorbed on two different types of active sites, whereas the dehydrogenation reaction for the acetone formation involves the initial adsorption of 2-propanol on one type of active site.
KW - Au-supported POMs
KW - Polyoxometalates
KW - Thermal 2-propanol oxidation
KW - Ti-substituted POMs
KW - in situ IR investigation
UR - http://www.scopus.com/inward/record.url?scp=84878715187&partnerID=8YFLogxK
U2 - 10.1002/pssb.201248405
DO - 10.1002/pssb.201248405
M3 - Article
AN - SCOPUS:84878715187
SN - 0370-1972
VL - 250
SP - 1165
EP - 1173
JO - Physica Status Solidi (B) Basic Research
JF - Physica Status Solidi (B) Basic Research
IS - 6
ER -