Bio-inspired Materials for Energy Storage Applications

Due to the immense demand for flexible supercapacitors, increasing amount of research is being done to develop low-cost and smart solutions. To date, electrodes made of ecofriendly materials have been either expensive or of limited use. This research investigates design, synthesis, and electrochemical evaluation of a novel class materials as electrodes. A group of solid-state, lightweight, low cost, and plant-based electrodes for supercapacitors are studied using experimental approaches. The biomaterial lignin is studied extensively for its use as an active material in those electrodes. For this purpose, the transition metal oxide MnOv2 and NiWOv4 nanoparticles are introduced to the lignin matrix, separately. To avoid the risks of using aqueous electrolytes, an organic gel polymer electrolyte PVA/Hv3POv4 is used. They show high specific capacitance values, with ~90% energy retention. The electrochemical performance exhibited by these lignin-based electrodes match the state-of-the-art results, and is superior in some cases. Due to the simplicity of the design process, these electrodes are a cost-effective option to the expensive eco-friendly materials currently in use. The remarkable electrochemical performance of these electrodes makes them useful for a wide variety of electronics. This new approach to fabricate electrodes from green sources, with simple processing and cost-effectiveness, marks an important step towards green energy technology development. This thesis includes 6 chapters. Following the first chapter of introduction and literature review, a hypothesis and a problem statement is discussed in the second chapter. The third chapter talks about the interaction of combining lignin with a transition metal oxide and the fourth chapter is a study on the effects of adding a biomaterial to this combination. In the fifth chapter, novel nanoparticles are introduced into the lignin matrix and their capacitive performance is studied. The final chapter analyzes the results obtained in this research and provides conclusions and recommended future studies