Dual-Copper Catalytic Site Formed in CuMFI Zeolite Makes Effective Activation of Ethane Possible Even at Room Temperature

被引：13

作者：

Itadani, Atsushi ^{[1
]}

Torigoe, Hiroe ^{[1
]}

Yumura, Takashi ^{[2
]}

Ohkubo, Takahiro ^{[1
]}

Kobayashi, Hisayoshi ^{[2
]}

Kuroda, Yasushige ^{[1
]}

机构：

[1] Okayama Univ, Grad Sch Nat Sci & Technol, Dept Fundamental Mat Sci, Kita Ku, Okayama 7008530, Japan

[2] Kyoto Inst Technol, Dept Chem & Mat Technol, Sakyo Ku, Kyoto 6068585, Japan

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2012年 / 116卷 / 19期

基金：

日本学术振兴会;

关键词：

MOLECULAR-ORBITAL METHODS; HIGH-SILICA ZEOLITES; EXTENDED BASIS-SETS; VALENCE BASIS-SETS; MFI-TYPE ZEOLITE; CARBON-MONOXIDE ADSORPTION; EXCHANGED ZSM-5 ZEOLITE; RAY ABSORPTION-EDGE; CU+ SITES; ION-EXCHANGE;

D O I：

10.1021/jp3022858

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The role of dual-cation sites in zeolites has received a renaissance in chemistry and industry directed toward fixation and activation of various gases; such sites may be expected to be more efficient than a single-cation site. We aimed to clarify the real active centers in the copper-ion-exchanged MFI-type zeolite (CuMFI) for ethane (C2H6). A peculiar feature was found in the appearance of the characteristic IR bands at 2644 and 2582 cm(-1) when C2H6 was adsorbed on Cu+ formed in CuMFI. The existence of dual species composed of two Cu+ ions bridging C2H6 was clearly indicated by extended X-ray absorption fine structure (EXAFS) data. Density functional theory calculations gave clear evidence that the two IR bands are distinctly due to C2H6 adsorbed on the dual-Cu+ site and not on a single site; this agrees with the EXAFS data. These data lead us to conclude that the dual-Cu+ site in the CuMFI sample is indispensable for efficient activation of C2H6 through the simultaneous interaction of C2H6 with two Cu+ ions.

引用

页码：10680 / 10691

页数：12