TY - JOUR
T1 - ZIF-8 with exceptional thermal stability
T2 - Role of organic cosolvents in phase control and structure stabilization
AU - Butt, Fraz Saeed
AU - Lewis, Allana
AU - Dingwall, Fergus
AU - Mazlan, Nurul A.
AU - Radacsi, Norbert
AU - Fan, Xianfeng
AU - Chen, Xianfeng
AU - Yang, Yaohao
AU - Yang, Shuiqing
AU - Huang, Yi
N1 - Funding Information:
This work was funded by Jiangsu Dingying New Materials Co., Ltd. under Grant Number [C−00005685] and the School of Engineering, the University of Edinburgh.
Funding Information:
This work was funded by Jiangsu Dingying New Materials Co., Ltd . under Grant Number [ C−00005685 ] and the School of Engineering, the University of Edinburgh.
Funding Information:
F.S.B. acknowledges the School of Engineering, The University of Edinburgh, and the Higher Education Commission of Pakistan for awarding a Ph.D. Scholarship.
Publisher Copyright:
© 2023 The Authors
PY - 2023/12
Y1 - 2023/12
N2 - Thermal stability is one of the key factors in catalysis and high-temperature industrial applications. The thermal degradation of ZIF-8, particularly its nanocrystals, could result in a significant loss of surface area and crystallinity, limiting its large-scale applicability. In this study, ZIF-8 nanocrystals with improved thermal stability were synthesized at room temperature (RT) through a facile, one-pot method – an ultrasound-assisted, solvent-guided ZIF-8 growth. The effect of synthesis variables, including the type and concentration of solvent, ultrasonication, and synthesis time, in improving the material's thermal stability was studied systematically. The as-prepared samples were analyzed by TGA/DSC, XRD, SEM/TEM, FTIR, and BET to monitor the weight loss with temperature, sample crystallinity, crystal morphology, chemical structure, and surface area. Notably, synthesis with 5 v/v% of n-hexane (ZIF-8new-ref) demonstrated the formation of highly-crystalline ZIF-8 nanocrystals with extraordinary thermal stability (with only ∼2.0–3.0 % weight loss up to 600 °C), large surface area (i.e., 975 m2 g−1), and an excellent particle size distribution in the range of 0.2–0.4 μm. More importantly, the short synthesis time (2 h) and sonication-assisted pretreatment of the precursor (for promoting solvent-ligand interaction) proved effective and played a crucial role in controlling ZIF-8's thermal stability. The mechanism for the thermal stability enhancement was thus proposed. The highly thermally stable ZIF-8 nanocrystals were also synthesized with significantly reduced chemical usage, e.g., 1/11 of the normal ligand-to-metal ratio (70), achieving cost-effective and environmentally friendly synthesis.
AB - Thermal stability is one of the key factors in catalysis and high-temperature industrial applications. The thermal degradation of ZIF-8, particularly its nanocrystals, could result in a significant loss of surface area and crystallinity, limiting its large-scale applicability. In this study, ZIF-8 nanocrystals with improved thermal stability were synthesized at room temperature (RT) through a facile, one-pot method – an ultrasound-assisted, solvent-guided ZIF-8 growth. The effect of synthesis variables, including the type and concentration of solvent, ultrasonication, and synthesis time, in improving the material's thermal stability was studied systematically. The as-prepared samples were analyzed by TGA/DSC, XRD, SEM/TEM, FTIR, and BET to monitor the weight loss with temperature, sample crystallinity, crystal morphology, chemical structure, and surface area. Notably, synthesis with 5 v/v% of n-hexane (ZIF-8new-ref) demonstrated the formation of highly-crystalline ZIF-8 nanocrystals with extraordinary thermal stability (with only ∼2.0–3.0 % weight loss up to 600 °C), large surface area (i.e., 975 m2 g−1), and an excellent particle size distribution in the range of 0.2–0.4 μm. More importantly, the short synthesis time (2 h) and sonication-assisted pretreatment of the precursor (for promoting solvent-ligand interaction) proved effective and played a crucial role in controlling ZIF-8's thermal stability. The mechanism for the thermal stability enhancement was thus proposed. The highly thermally stable ZIF-8 nanocrystals were also synthesized with significantly reduced chemical usage, e.g., 1/11 of the normal ligand-to-metal ratio (70), achieving cost-effective and environmentally friendly synthesis.
KW - Cosolvent-assisted synthesis
KW - Cost-effective synthesis
KW - Thermal stability
KW - Zeolitic imidazolate frameworks (ZIFs)
KW - ZIF-8 nanocrystals
UR - http://www.scopus.com/inward/record.url?scp=85177210422&partnerID=8YFLogxK
U2 - 10.1016/j.mtchem.2023.101804
DO - 10.1016/j.mtchem.2023.101804
M3 - Article
AN - SCOPUS:85177210422
SN - 2468-5194
VL - 34
JO - Materials Today Chemistry
JF - Materials Today Chemistry
M1 - 101804
ER -