Synthesis of novel carbon materials for supercapacitor applications

• Autor(a) principal: Soltani, Paniz
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/22368
• topic: Supercondensadores; Armazenamento de energia; Grafeno; Electroquímica; Componentes electrónicos; Química

Micro-supercapacitors (MSCs) are the key components of miniaturized, portable and wearable electronic devices. Although many advances have been made in this field during the recent years, micro-supercapacitors energy density remains far from those from lithium-ion batteries and electrolyte capacitors. Many efforts have been made to improve MSCs performances such as fabrication of nanostructures and thin-film manufacture technologies. Here, we demonstrated MSCs based on porous carbon and PEDOT: PSS polymer as well as RuO2 and electrochemically exfoliated graphene. Combining materials with pseudo capacitive and electrochemical double layer capacitance ability, the resulting MSCs deliver an area capacitance up to 1mFcm-2 and stack capacitance up to 51 Fcm-3 for graphene based devices and area capacitance up to 203 μFcm-2 and stack capacitance up to 12 Fcm-3 for polymer based devices. Both devices show ability to be operated in ultra-high rates up to 1000 Vs-1 which is around three orders of magnitude higher that of conventional batteries. The high capacitance is generally obtained at low scan rates (~ 10 mVs-1) and 40% of capacitance retention has been observed.