| Summary: | This thesis details the preparation, fabrication and characterization of nanostructured carbonaceous materials with tuneable porosity for gas storage (CO2 and H2) applications. Two types of carbon-based materials were investigated, namely zeolite templated carbons (ZTCs) and activated carbons (ACs). The ZTCs were prepared using zeolite 13X and zeolite Y as hard templates and furfural alcohol, ethylene, and acetonitrile as carbon precursors. The effects of zeolite compaction before use as hard templates were investigated through the compression of powder forms of zeolites at 370 MPa (equivalent to 5 tonnes) or 740 MPa (equivalent to 10 tonnes) prior to their use as templates. A combination of liquid impregnation (LI) with furfural alcohol and chemical vapour deposition (CVD) with ethylene, or acetonitrile was used to deposit the carbon precursor.
Activated carbons (ACs) were prepared using KOH as activating agent from various carbon precursors namely, (i) Eucalyptus wood sawdust (as a cheap, green, renewable and abundantly available raw material), (ii) Lignin-derived carbonaceous matter, (iii) Polythiophene as a sulphur-rich polymer, and (iv) Polypyrrole as a Nitrogen-rich polymer. The activated carbons were prepared via two different routes; (1) activation via thermal treatment of a powder mixture of starting materials and activating agent (KOH) or (2) compactivation (or mechanochemical activation) wherein the mixture of the starting material and KOH is compacted at 5 tonnes (equivalent to 370 MPa) or 10 tonnes (equivalent to 740 MPa) into a pellets/disks prior to activation. The compactivation route was found to be more efficient as it reduces/ removes interparticles voids and space between solid-solid and thus enhances chemical interaction between the precursor and KOH, and also improves both the porosity and the bulk density of the resulting activated carbon.
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