TY - JOUR
T1 - Exfoliation of Metal-Organic Framework Nanosheets Using Surface Acoustic Waves
AU - Liu, Xia
AU - Jia, Qinxiang
AU - Fu, Yongqing
AU - Zheng, Tengfei
N1 - Funding information: This work was supported by Natural Science Foundation of China (No.51805427), Shaanxi Provincial Natural Science Foundation (Grant No. 2019JM-242), the Engineering Physics and Science Research Council of UK (EPSRC EP/P018998/1) and International Exchange Grant (IEC/NSFC/201078) through Royal Society and the NSFC.
PY - 2022/2/7
Y1 - 2022/2/7
N2 - Two-dimensional (2D) metal-organic framework (MOF) nanosheets have recently received extensive attention due to their ultra-thin thickness, large specific surface area, chemical and functional designability. In this study, an unconventional method using surface acoustic wave (SAW) technology is proposed to exfoliate large quantities and uniform layers of 2D MOF-Zn2(bim)4 nanosheets in a microfluidic system. We successfully demonstrated that the thickness of 2D MOF is effectively and accurately controlled by optimizing the SAW parameters. The mechanisms for the efficient exfoliation of 2D MOF nanosheets is attributed to both the electric and acoustic fields generated by the SAWs in the liquid. The electric field ionizes the methanol to produce H + ions, which intercalate Zn2(bim)4 sheets and weaken the interlayer bonding, and the strong shear force generated by SAWs separates the MOF sheets. A yield of 66% for monolayer MOFs with a maximum size of 3.5 μm is achieved under the combined effect of electric and acoustic fields. This fast, low-energy exfoliation platform has the potential to provide a simple and scalable microfluidic exfoliation method for production of large-area and quantities of 2D MOFs.
AB - Two-dimensional (2D) metal-organic framework (MOF) nanosheets have recently received extensive attention due to their ultra-thin thickness, large specific surface area, chemical and functional designability. In this study, an unconventional method using surface acoustic wave (SAW) technology is proposed to exfoliate large quantities and uniform layers of 2D MOF-Zn2(bim)4 nanosheets in a microfluidic system. We successfully demonstrated that the thickness of 2D MOF is effectively and accurately controlled by optimizing the SAW parameters. The mechanisms for the efficient exfoliation of 2D MOF nanosheets is attributed to both the electric and acoustic fields generated by the SAWs in the liquid. The electric field ionizes the methanol to produce H + ions, which intercalate Zn2(bim)4 sheets and weaken the interlayer bonding, and the strong shear force generated by SAWs separates the MOF sheets. A yield of 66% for monolayer MOFs with a maximum size of 3.5 μm is achieved under the combined effect of electric and acoustic fields. This fast, low-energy exfoliation platform has the potential to provide a simple and scalable microfluidic exfoliation method for production of large-area and quantities of 2D MOFs.
KW - metal-organic framework (MOF- Zn2(bim)4) nanosheets
KW - surface acoustic wave(SAW)
KW - electric field
KW - Surface acoustic wave(SAW)
KW - Metal–organic framework (MOF- Zn(2)(bim)(4)) nanosheets
KW - Electric field
U2 - 10.1016/j.ultsonch.2022.105943
DO - 10.1016/j.ultsonch.2022.105943
M3 - Article
SN - 1350-4177
VL - 83
JO - Ultrasonics Sonochemistry
JF - Ultrasonics Sonochemistry
M1 - 105943
ER -