3. Result and discussion
3.1. Structural properties of the porous carbons
The activated carbon samples obtained by carbonization of the
pre-carbonized biomass with a chemical activator (KOH) were of
black color consistent with a completely carbonized product. The
microstructures of samples are shown in Fig. 1. When these materials
are examined using FE-SEM, interesting features are observed.
The FE-SEM micrographs of the activated carbon samples reveal
the presence of abundant pores generated during carbonization
using activating agents. Irrespective of the precursor’s combination,
all samples exhibit an identical morphology that is characterized
by regular shaped pores with wide net nested cavities
(Figs. 1A –C and S1). These results show that a morphological
improvement has occurred through the activation process, and a
lot of porosity is comprised of randomly oriented microspores as
detected in the HR-TEM micrographs of the activated carbon
samples shown in Figs. 1D –F and S2.
The microstructures of the activated carbon samples were analyzed
via nitrogen adsorption/desorption isotherms as shown in
Fig. 2. N2 sorption isotherms and pore size distribution (PSD) of
the activated carbons are obtained from the chemical activation
(precursors/KOH = 1/4) of the porous carbon samples prepared
from gelatin and starch mixed together at different ratios. The
sorption isotherms are of comparable shape and exhibit Type I
isotherm according to the International Union of Pure and Applied Chemistry (IUPAC) classification. The pore size distribution (PSD) indicates that the porosity of these activated carbons consistsmainly of micropores and a few mesopores.