ABSTRACT
This work is aimed at studying activated carbons as supercapacitor
electrode materials derived from plant biomass waste materials. The
activated carbon raw materials are sourced from coconut shell, pine cone
and rice husk plant biomass. The chemical activation route is
employed with KOH as an activating agent. The carbonization
temperature used is 800 oC and the carbonization time is varied from 1 h
to 5 h. Activated carbon of high surface area and porosity are achieved
and their electrodes show a good electrochemical performance presenting
them as applicable for supercapacitor electrode materials.
CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND
As the global economy constantly continues to rise, the global demand
for power and energy sources are synonymously increasing. This raises
the consumption of fossil fuels which produces two major related issues;
depletion of fossil fuel reserves and environmental greenhouse emission
problems which not only pose pollution problems but also climate change
issues. These issues have been projected as one of the global urgent
and important challenges to be tackled. There is, therefore, a need to
develop alternative energy sources that are clean, sustainable, and meet
up with the rising global demand. In view of this, a lot of renewable
energy sources have been explored but they generally have a commonly
associated issue; they are seasonal. Most renewable clean energy sources
are highly dependent on the time of day and regional weather
conditions. The need for the development of related energy conversion
and energy storage devices, therefore, arises in order to take the
harnessing of these renewable clean energy sources to their best
efficiency. Energy conversion and storage devices showing the greatest
potentials currently include; batteries, supercapacitors and fuel cells
[1].
1.2 MOTIVATION AND PROBLEM STATEMENT
Supercapacitors are yet to reach their full potential even as energy
storage problems persist. Supercapacitors are governed by the same
fundamental equations as conventional capacitors, but utilizing higher
surface area electrodes and thinner dielectrics to achieve greater
capacitances seem to possess the quality for future energy solutions.
Fossil-based carbon sources for application as activated carbon
materials are limited and non- renewable; biomass-based sources are
low-cost high-performance candidates.
1.3 SCOPE AND OBJECTIVE
This work is aimed at studying activated carbon which can serve as
the negative electrode material of asymmetric supercapacitors. The
activated carbon is sourced from biomass materials of pine cones, rice
husks, and coconut shells. The electrochemical and surface area
parameters of activated carbon are studied and a comparative study of
the different materials is presented with suggested optimization
techniques.