Hydrothermal Treatment to Produce Honeycomb-like Structure of Hierarchical Carbon from Intsia, spp Waste Wood: Preparation and Characterisation

Abstract

Hydrothermal treatment of Intsia, spp wood waste has succeeded in producing hierarchical carbon structures such as honeycomb-like structures. This study aims to examine the difference between hydrothermal and non-hydrothermal activation treatments in the hierarchical synthesis of carbon. Sequentially, the hydrothermal treatment was created with ZnCl₂ as an activating agent and H₂O₂ as an oxidising agent. The hydrothermal process is followed by carbonisation at 700\(^{\circ}\) C under N₂ gas (HC-ZH) and oxidation at 350\(^{\circ}\) C  in an oxygen stream (HC-ZH-Ox). All carbonised products were analysed using XRD, FT-IR, the Boehm method to determine the quantity of oxygenated functional groups (OFGs), the NH₃ base gas adsorption method to determine the total acid amount, and the Surface Area Analyser (SAA) and SEM. Hierarchical carbon with the amorphous structure shown by XRD analysis. Hydrothermal treatment increased the OFGs content, 50.25% for carboxylic groups, 354.62% for phenolic groups, and 3.9% for lactone groups. The presence of OFGs was proven through identification using FTIR. Hydrothermal treatment increased acidity by 387.83%, the highest surface area produced by hierarchical carbon non-hydrothermal (HC-Ox) of 443.5 (m²/g). The HC-ZH-Ox has a surface area of 232.2 (m²/g). SEM image shows a structure of stacked honeycomb-like, with different thicknesses in the samples HC-ZH-Ox and HC-Ox.