Highly mesoporous single-crystalline zeolite beta synthesized using a nonsurfactant cationic polymer as a dual-function template.
Mesoporous zeolites are useful solid catalysts for conversion of bulky molecules because they offer fast mass transfer along with size and shape selectivity. We report here the successful synthesis of mesoporous aluminosilicate zeolite Beta from a commercial cationic polymer that acts as a dual-function template to generate zeolitic micropores and mesopores simultaneously. This is the first demonstration of a single nonsurfactant polymer acting as such a template. Using high-resolution electron microscopy and tomography, we discovered that the resulting material (Beta-MS) has abundant and highly interconnected mesopores. More importantly, we demonstrated using a three-dimensional electron diffraction technique that each Beta-MS particle is a single crystal, whereas most previously reported mesoporous zeolites are comprised of nanosized zeolitic grains with random orientations. The use of nonsurfactant templates is essential to gaining single-crystalline mesoporous zeolites. The single-crystalline nature endows Beta-MS with better hydrothermal stability compared with surfactant-derived mesoporous zeolite Beta. Beta-MS also exhibited remarkably higher catalytic activity than did conventional zeolite Beta in acid-catalyzed reactions involving large molecules.
Key Lab of Applied Chemistry of Zhejiang Province, Department of Chemistry, Zhejiang University , Hangzhou 310028, China.
Jie
J
Zhu
Yihan
Y
Zhu
Liangkui
L
Zhu
Marcello
M
Rigutto
Alexander
A
van der Made
Chengguang
C
Yang
Shuxiang
S
Pan
Liang
L
Wang
Longfeng
L
Zhu
Yinying
Y
Jin
Qi
Q
Sun
Qinming
Q
Wu
Xiangju
X
Meng
Daliang
D
Zhang
Yu
Y
Han
Jixue
J
Li
Yueying
Y
Chu
Anmin
A
Zheng
Shilun
S
Qiu
Xiaoming
X
Zheng
Feng-Shou
FS
Xiao