Studies on the development and characterisation of carbon-based materials for energy applications

<p></p>Continuing reliance on fossil fuels, in particular coal, accompanied by growth in the global population, has caused rising carbon dioxide emission leading to global warming. Currently, ~85% of global primary energy requirement relies on fossil fuels. In addition, according to the international energy agency (IEA) report, the oil supply will surpass the consumption of oil peak by 2035. Renewable energy resources are one of the options to tackle climate change. Therefore, the search for sustainable and clean energy is pressing and needs to be urgently implemented. Various renewable resources such as solar, wind, tidal, hydro, biomass, and geothermal are being implemented to satisfy the global energy demand. Among all existing resources, hydrogen appears as a next-generation future fuel and meets all the energy demands and offers a diversified supply.<p></p> <p></p>Hydrogen-based technologies for energy storage and resupply have emerged as a clean, zero greenhouse gas emission, and safe means of ensuring continuous supply from inherently variable renewable energy resources across a range of stationary and mobile applications. A key technology for efficiently converting stored hydrogen gas into electricity is the polymer electrolyte membrane (PEM) fuel cell, which operates at low temperature (< 80°C), provides a quick start up and has a relatively high energy efficiency and power density.<p></p> <p></p>The present thesis addresses two topics relevant to the future development of hydrogen energy technologies: (1) optimising gas diffusion layers in PEM fuel cells; and (2) carbon nitride storage materials for a `proton battery'. These two research components were conducted at different locations as part of the AcSIR PhD exchange program between India and Australia.<p></p> <p></p>Hence the first component of the present thesis has sought to contribute to closing this research gap by investigating ways to improve the performance and efficiency of PEM fuel cell by optimising the pre-requisite properties of GDLs fabricated from non-woven carbon fibre composite sheet. This component has been conducted at CSIR- National Physical Laboratory, New Delhi, India. The second component of the thesis has focussed on another key aspect of PEM fuel cell systems: the storage of hydrogen required as the input fuel.<p></p>