A multi-dimensional quasi-zeolite with 12 × 10 × 7-ring channels demonstrates high thermal stability and good gas adsorption selectivity

Jie Liang; Wei Xia; Junliang Sun; Jie Su; Maofeng Dou; Ruqiang Zou; Fuhui Liao; Yingxia Wang; Jianhua Lin

doi:10.1039/c5sc04916d

A multi-dimensional quasi-zeolite with 12 × 10 × 7-ring channels demonstrates high thermal stability and good gas adsorption selectivity

Chem Sci. 2016 May 1;7(5):3025-3030. doi: 10.1039/c5sc04916d. Epub 2016 Jan 25.

Authors

Jie Liang^{1

2}, Wei Xia³, Junliang Sun^{1

2}, Jie Su², Maofeng Dou⁴, Ruqiang Zou³, Fuhui Liao¹, Yingxia Wang¹, Jianhua Lin¹

Affiliations

¹ College of Chemistry and Molecular Engineering , Peking University , Beijing , 100871 , China . Email: yxwang@pku.edu.cn ; Email: junliang.sun@pku.edu.cn.
² Berzelii Center EXSELENT on Porous Materials and Inorganic and Structural Chemistry , Department of Materials and Environmental Chemistry , Stockholm University , Stockholm , 10691 , Sweden.
³ College of Engineering , Peking University , Beijing , 100871 , China.
⁴ Department of Materials Science and Engineering , Royal Institute of Technology , Stockholm , 10044 , Sweden.

Abstract

A novel quasi-zeolite PKU-15, with a rare 3-dimensional structure containing interconnected large (12-ring), medium (10-ring) and small (7-ring) multi-pore channels, was hydrothermally synthesised and characterised. A unique tri-bridging O^2- anion is found to be encapsulated in the cage-like (Ge,Si)₁₂O₃₁ building unit and energetically stabilises the PKU-15 framework. The removal of this oxygen atom would convert PKU-15 into a hypothetical zeolite PKU-15H. Thus, PKU-15 can be considered as a unique 'quasi-zeolite', which bridges porous germanates and zeolites. Owing to the absence of terminal Ge-OH groups in its structure, PKU-15 shows a remarkably high thermal stability of up to 600 °C. PKU-15 is also the first microporous germanate that exhibits permanent porosity, with a BET area of 428 m² g^-1 and a good adsorption affinity toward CO₂.