title: Improving the Loading Capacity of Metal-Organic Framework Thin Films Using Optimized Linkers.
abstract: The large surface area of metal-organic frameworks (MOFs) sparks great interest for their use in storage applications. While the bulk of MOF applications focuses on incorporation of gases, we demonstrate that these highly porous frameworks are also well-suited for metal ion storage. For well-defined, highly oriented surface-anchored MOF thin films grown on modified gold surfaces using liquid-phase epitaxy (LPE), also referred to as SURMOFs, we determined the loading of two different types of MOF materials with a total of seven types of metal ions (Zn(2+), Ag(+), Pd(2+), Fe(3+), Cd(2+), Ni(2+), and Co(2+)). Measurements using a quartz crystal microbalance (QCM) allowed determination of loading capacities as well as diffusion constants in a quantitative fashion. The adsorption capacities were observed to be highly ion specific; the largest uptake was for Fe(3+) and Pd(2+) ions with six and four metal ions per MOF pore, respectively. By comparing results for SURMOFs fabricated from different types of linkers, we demonstrate that S-containing functionalities in particular drastically improve the storage capacity of MOFs for metal ions.
authors: Karlsruhe Institute of Technology and Institute of Functional Interfaces (IFG) , Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.|State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology , Luoshi Road #122, Wuhan 430070, P.R. China.
authors: Wei
authors: W
authors: Guo
authors: Department of Biology and Chemistry, City University of Hong Kong , 83 Tat Chee Avenue, Kowloon, Hong Kong, P.R. China.
authors: Meiqin
authors: M
authors: Zha
authors: Karlsruhe Institute of Technology and Institute of Functional Interfaces (IFG) , Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
authors: Zhengbang
authors: Z
authors: Wang
authors: Karlsruhe Institute of Technology and Institute of Functional Interfaces (IFG) , Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
authors: Engelbert
authors: E
authors: Redel
authors: Department of Biology and Chemistry, City University of Hong Kong , 83 Tat Chee Avenue, Kowloon, Hong Kong, P.R. China.
authors: Zhengtao
authors: Z
authors: Xu
authors: Karlsruhe Institute of Technology and Institute of Functional Interfaces (IFG) , Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
authors: Christof
authors: C
authors: Wöll
keywords: MOF; SURMOF; ion uptake; optimized linkers; quartz crystal microbalance