Ibrahim Abouelamaiem, Dina; (2018) Exploring the Synergy of Functionalised Bio-carbons and their Performance in Supercapacitor Devices. Doctoral thesis (Ph.D), UCL (University College London).

Preview

Text Dina Ibrahim_Final Thesis.pdf Download (11MB) | Preview

Abstract

Supercapacitors have gained increasing interest due to their complementary performance to batteries and fuel cells. The electrochemical device has proven to provide exceptional performance through enhancing the electrode materials, exploration of potential electrolyte solutions, integration in new cell designs and therefore improving their performance to meet the needs of high energy and power requirements. However, there is little insight of the complex, multi-dimensional characterisation and correlation between the porous carbon structures generally exploited as electrode materials, and deviation-from-ideality performance in electrical double layer capacitors. The investigation from functionalisation of countless bio-carbons and their application in supercapacitor devices, to the prospective electrochemical dynamics in supercapacitors is not well established. In this thesis, one-, two- and three-dimensional characterisation techniques, in combination with electrochemical quantification of activated cellulose carbons are used to tackle the effect of porous carbon structures on the behaviour of symmetric carbon supercapacitors. Non-ideal mechanisms were examined using the electrochemical impedance spectroscopy technique to quantify capacitances and relaxation times’ variation in wide frequency ranges across different carbonaceous morphologies. Extreme voltage conditions were employed and characterised with in-situ Raman spectroscopy to identify the electrode state-of-art and a critical reasoning for different performance rates. A printed circuit board design has been suggested as a promising device for the application of supercapacitors and possible integration with other electrochemical cells. The experimental evaluations reported herein classify unreported affiliation between diversified architectural and electrochemical features. The interplay between structural dynamics and electrochemistry at standard and extreme conditions are described, highlighting the interpretation and importance of assessing non-ideal behaviour in supercapacitors. A new engineering approach for supercapacitor devices is revealed that opens a platform for hybridized systems in a well-known design. These perceptions are expected to be adapted for a better understanding of the framework of different supercapacitor devices and consideration of new design models.

Download activity - last month

Export as XMLJSONCSV

Download activity - last 12 months

Export as CSVXMLJSON

Downloads by country - last 12 months

Export as CSVJSONXML

Archive Staff Only

View Item