Boosting the Ceramics with In Situ MOF-Derived Nanocarbons

Abstract

Metal–organic framework (MOF)-derived nanocarbons have emerged as promising materials for energy and environmental applications owing to their high surface area, structural and chemical tunability, and hierarchical porosity. Although various carbon-based materials such as graphene and carbon nanotubes have been extensively used as secondary sintering additives to develop advanced ceramics with improved mechanical, thermal, and electrical properties, the potential of MOF-derived nanocarbon-based materials has not been explored. Here, we report the first use of MOF-derived nanocarbons as a reinforcement phase in ceramic composites. To this end, Al2O3 and zeolitic imidazolate framework (ZIF-8) are used as the ceramic matrix and nanocarbon source, respectively. The ceramic composites are produced by densifying Al2O3 and ZIF-8 powder mixtures using spark plasma sintering (SPS) at 1550 °C and uniaxial pressure of 50 MPa. The fracture toughness of the composite increases up to 67% in comparison to an alumina monolith as ZIF-derived nanocarbons form interlayers to assist the dissipation of energy during the crack propagation and inhibit grain growth. The room-temperature electrical conductivity of the sintered samples drastically increases with the in situ formed nanocarbon-based fillers, reaching as high as 1410 S/m for 10 wt % ZIF-8 content. These results constitute an excellent initial step toward boosting the mechanical and electrical properties of ceramic matrix composites with in situ MOF-derived nanocarbons.

Enhancing the Properties of Yttria-Stabilized Zirconia Composites with Zeolitic Imidazolate Framework-Derived Nanocarbons

“…Previously, our research successfully showcased the value of MOF as a source of nanocarbon reinforcement in CMCs through the use of spark plasma sintering (SPS), a highly effective powder consolidation method . Our findings indicated that when zeolitic imidazolate framework (ZIF-8) nanopowder was uniformly dispersed within an Al 2 O 3 matrix in solid form, it underwent an in situ transformation into graphitic carbon during the sintering process.…”

“…Our findings indicated that when zeolitic imidazolate framework (ZIF-8) nanopowder was uniformly dispersed within an Al 2 O 3 matrix in solid form, it underwent an in situ transformation into graphitic carbon during the sintering process. The resulting composites exhibited notably enhanced fracture toughness and electrical conductivity relative to pure sintered Al 2 O 3 . Building upon this innovative concept, this study extends its application to other ceramic matrices and MOFs.…”

Metal‐Organic Frameworks‐Derived Nanocarbon Materials and Nanometal Oxides for Photocatalytic Applications

“…[68][69][70] For metals with higher boiling points, any residual metal can be removed through acid washing, leading to the generation of MOFs-derived nanocarbon materials. [71,72] Calcination of MOFs in air or oxygen atmosphere may lead to partial or complete decomposition and volatilization of organic components. Complete removal results in MOFsderived nanometal oxides, while partial removal yields MOFsderived nanometal particle/nanocarbon composite materials.…”