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ur previous work investigated the templating ability of graphene oxide-derived additives to induce graphitization of the novolac matrix. The findings led to two working hypotheses: the additives act as templates that promote matrix aromatic alignment to their basal planes during carbonization (referred to here as physical templating) in addition to forming radical edge sites that bond to the decomposing matrix (referred to here as chemical templating). However, results mainly underscored the role of functional groups on the GO additives (chemical templating). The aim of this current work seeks to differentiate the contributions of the operative mechanisms on graphitization. To study this, 2D materials with minimal oxygen functionalization, graphene and hexagonal boron nitride (hBN) were used as templates to induce graphitization of novolac matrix. First, the optimum weight percent of the 2D materials was determined with the composite graphitic quality measured by X-ray diffraction and Raman spectroscopy. Results revealed that hBN did not induce graphitization of novolac and was attributed to the absence of a sp² framework in hBN, unable to provide the crucial π-π interactions with the aromatic rings of the matrix. In contrast, the graphene additives mirrored one another and showed improved graphitization of the novolac. From these results, it was surmised that both mechanisms are operative; while physical templating offers control over long-range order in the form of crystallite height, chemical templating contributes to carbon reorganization and lateral growth extent. 

Pressurized carbonization is known to improve carbon content and create textural changes in resultant carbon compared to conventional (atmospheric) carbonization. However, further studies investigating the impact of these carbonization methods on the graphitic quality of the carbon precursors have not been explored exten- sively. This study investigates the influence of carbonization methods on the graphitization behavior of soft and hard carbons using a three-model system: phenolic resole (hard carbon), polyvinyl chloride (PVC) (soft carbon), and a 50:50 blend of resole and PVC. Carbonization was conducted under autogenic pressure (AGP) and at- mospheric pressure (APP) at 500◦C for 5 h, followed by high-temperature treatment at varying temperatures. Various techniques, including X-ray diffraction and Raman spectroscopy showed hard carbon precursors exhibited improved properties under AGP carbonization such as larger crystallite size, sharp crystalline peaks, lower ID/IG ratio, and narrow G-full width half-maximum, an indication of improved crystallinity by lowering amorphous phase at high temperature. For soft carbon precursors, the method of carbonization did not impact the graphitization level. The most significant finding was the enhanced crystalline nature observed in hard carbon under AGP conditions, without the need for any catalyst. It shows the influence of pressure on improving the crystallinity of hard carbon precursors.