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Updated: Feb 7, 2026
Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Controllable formation of meso- and macropores within metal-organic framework crystals via a citric acid modulator
Ting Liu1, Yongxin Liu, Lili Yao
1Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New-Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China. cwang@tjut.edu.cn.
Abstract:
Citric acid (CA) is introduced to modulate the synthesis of octahedral HKUST-1 (also known as Cu3(BTC)2, BTC = benzene-1,3,5-tricarboxylate) particles with hierarchical micro, meso- and/or macropores (noted as HP-HKUST-1 particles) under mild conditions. The particle size of the resultant product could be tuned from 300 nm to 2.4 μm by varying the amount of CA added, solvents, reaction time and so on. The intrinsic microporous structure of HKUST-1 is maintained despite the strong chelation capability of CA towards Cu2+ while the larger pores' size is in the range of 30 to 100 nm. The possible formation mechanism of these octahedral HP-HKUST-1 particles is proposed on the basis of our systematic investigations. The resulting micrometer HP-HKUST-1 particle is employed to encapsulate phosphomolybdic acid hydrate (HPMo), a catalyst for the methanolysis of styrene oxide. After encapsulation, a superior catalytic activity with a high conversion rate (99.6%) is achieved when the reaction is carried out at 40 °C for 20 min.
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