The
key feature of the present work is the dexterous utilization
of an apparently destructive process, pyrolysis, for the synthesis
of the most esteemed nanomaterial, graphene. This work is an attempt
to synthesize graphene from nonconventional sources such as tannic
acid, alginic acid, and green tea by a controlled pyrolysis technique.
The precursors used in this work are not petroleum-derived and hence
are green. A set of pyrolysis experiments was carried out at different
temperatures, followed by a thorough step-by-step analysis of the
product morphology, enabling the optimization of the graphitization
conditions. A time-dependent morphological analysis was also carried
out along with isothermal thermogravimetric studies to optimize the
ideal pyrolysis time for graphitization. The specific capacitance
of the graphene obtained from alginic acid was 315 F/g, which makes
it fairly suitable for application as green supercapacitors. The same
graphene was also used to fabricate a rubber-latex-based flexible
supercapacitor film with 137 F/g specific capacitance. The graphene
and graphene-based latex film exhibited room-temperature magnetic
hysteresis, indicating their ferromagnetic nature, which also supports
their spintronic applications.