In Situ Thermal Conductivity Measurement of Single-Crystal Zeolitic Imidazolate Framework-8 by Raman-Resistance Temperature Detectors Method

Abstract

The thermal conductivity measurement of metal−organic frameworks (MOFs), which plays an important role in thermal management of MOF-based gas separation, storage, and thermal energy conversion (e.g., adsorption heat pumps), has been a challenging task for decades. However, the direct thermal conductivity measurement of a single-crystal MOF is currently limited by their small crystal sizes, since no sophisticated approach has ever been reported. In this study, the Raman-resistance temperature detectors (Raman-RTDs) method was developed for in situ measuring of the thermal conductivity of single-crystal ZIF-8, whose system error resulting from the thermal contact resistance between sample and RTDs can be eliminated. According to the dependence of thermal resistance of MOF crystals on the laser spot location, the thermal conductivities of polycrystalline and single-crystal ZIF-8 were derived to be 0.21 ± 0.03 and 0.64 ± 0.09 W/(m•K), respectively. The proposed in situ thermal conductivity measurement method may be further extended to other types of microscale particles.

Molecular Insights into the Correlation between Microstructure and Thermal Conductivity of Zeolitic Imidazolate Frameworks

“…13 The measured thermal conductivities of ZIF-8 (i.e., 0.326 W m −1 K −1 ), 11 UiO-66 (i.e., 0.11 W m −1 K −1 ), 13 UiO-67 (i.e., 0.19 W m −1 K −1 ), 13 Cu-BTC (i.e., 0.39 W m −1 K −1 ), 13 and perovskite-like MOF-1 (i.e., 1.3 W m −1 K −1 ) 14 at room temperature are commonly low. Due to the limitation of the conventional steady-state measurement, it is very challenging to directly obtain the thermal conductivity of a single MOF crystal with a size below several millimeters 15 by excluding the thermal contact resistance between MOF crystals. Therefore, current thermal conductivity measurement techniques cannot satisfy our requirements to reveal the microscale heat transfer mechanism within MOF frameworks.…”

Effect of Phase Transition on the Thermal Transport in Isoreticular DUT Materials

“…However, compared with the gas adsorption property, the study of the thermal transport in SPCs is still in its very early stage. To date, only the thermal conductivity of some conventional SPCs such as MOF-5, − ZIF-8, − and HKUST-1 ,, has been investigated in detail by experimental or computational approaches, while the thermal transport properties of the aforementioned DUT series still remain unknown. In addition, the existing studies mainly focus on the influence of gas and water adsorption, , framework architecture, ,,− defects, and physical environment including pressure and temperature on the thermal conductivity of SPCs; little attention has been paid to the evolution of the thermal transport properties of SPCs during their dynamic process, i.e., the phase transition.…”

Total Bioaerosol Detection by Split Aptamer-Based Electrochemical Nanosensor Chips

“…By taking advantage of the excellent electrical conductivity of MXenes and the extremely large surface area of metal–organic frameworks (MOFs), three-dimensional MOFs@MXene composites were prepared, which allowed us to amplify the transduced electrochemical signal following biorecognition to improve the assay sensitivity. Zeolitic imidazolate frameworks (i.e., ZIF-8) were used here due to their high thermal and chemical stability . We further demonstrated the utility of the SAE-nChip for bioaerosol detection in a practical context.…”