Evaluation of sustainability of fabrication process and characterization studies of activated carbon nanocatalyst from waste chestnut peels

Abstract

This study uses waste chestnut peels to synthesize low-cost activated carbon-based catalysts through pyrolysis and calcination, investing distinct structural and compositional variations for sustianble application in manufacturing innovation and allied industries. The X-ray diffraction (XRD) analysis indicated sharp crystalline peaks in the calcinated product, contrasting with the amorphous nature of carbon material with some partially crystalline and distorted graphitic phases of the pyrolyzed product. Fourier-transform Infrared spectroscopy (FT-IR) analysis shows the presence of various functional groups such as O–H, C–O, C–H, CO, and CC. The analysis made through the scanning electron microscope (SEM) and transmission electron microscope (TEM) depicted a packed and agglomerated structure with different irregular particle shapes in the calcined carbon, while the sample prepared through pyrolysis exhibited a network-like structure with some interconnected voids. Energy dispersive X-ray (EDX) analysis showed varying carbon content which is found to be 47.41 % in the case of the calcinated sample and 99.7 % in the product prepared through pyrolysis. The calcined carbon exhibited a band gap of 4 eV, while the pyrolyzed carbon showed a higher band gap of 4.8 eV. In addition, the catalyst prepared through the calcination process exhibited significantly higher luminance intensity than that produced through pyrolysis, while both samples showed an excitation-dependent emission property. This work presents two simple methods for synthesizing nanocarbon-based catalysts using waste lignocellulosic biomass. In addition, the optical properties of the resulting nanocarbons suggest that they can be further explored for their applications as catalysts or biosensing agents.