Carbon derived electrodes and electrolytes for electrochemical energy systems

Abstract

The world is witnessing the inconsiderate consumption of fossil fuels which are responsible for catastrophic climate change and global warming Therefore renewable energy sources wind solar hydropower biomass etc play significant roles in generating electrical power from their infinite resources These resources have advantages over non renewable resources in terms of environmental impacts and sustainability However there exists a visible mismatch between energy demand and energy supply due to the intermittent nature and temporal variations of renewable energy resources and it is well documented that electrochemical energy devices can serve as efficient tools to bridge this gap In the context of electrochemical energy devices carbon materials have shown their various advantages as electrodes and electrolytes because of their desirable properties like high electrical conductivity high thermal stability ability to conduct protons ability to function as molecular fuel barriers etc However in the context of aqueous metal ion batteries utilization of carbon materials as electrodes often lead to spontaneous de insertion reactions undesirable proton insertions reactions leading to parasitic hydrogen evolution reactions unwanted swelling etc Aqueous redox flow batteries mainly suffer from their inferior energy density derived from the underutilization of dissolved electroactive species and even the employment of high surface area carbon nanotube electrodes often fail to overcome these hurdles With regard to energy conversion devices such as water electrolysers and fuel cells though it is predicted that graphene oxide can conduct protons and can function as effective barrier for molecular fuels these materials have not been explored in their pristine form to shuttle protons in a practical reversible fuel cell Therefore the primary aim of this thesis is to incorporate carbon derived materials into the architectural configuration of electrochemical energy devices as electrodes in energy storage devices and as elec