Simultaneous reduction of carbon dioxide and energy harvesting using RGO-based SiO2-TiO2 nanocomposite for supercapacitor and microbial electrosynthesis

• Published in: Applied catalysis. B, Environmental Vol. 339; p. 123091
• Main Authors: Anwer, Abdul Hakeem, Shoeb, Mohd, Mashkoor, Fouzia, Ali, Aleesha, Kareem, Sumairah, Ansari, Mohd Zahid, Park, Jang Min, Jeong, Changyoon
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2023
• Subjects: Bio-photocatalysis; Carbon dioxide sequestration; Energy Harvest; Nanocomposite; Supercapacitor; Bio-photocatalysis; Supercapacitor; Energy Harvest; Carbon dioxide sequestration; Nanocomposite
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2023.123091

Nowadays, developing a simple, economical, and scalable approach for producing energy storage and harvesting devices remains challenging. Herein, we developed a mesoporous RGO-SiO2-TiO2 nanocomposite for the electroreduction of carbon dioxide through microbial electrosynthesis and high-performance supercapacitor device. An electrode containing Si/Ti oxide nanoparticles and a layer of RGO coated on carbon felt containing RGO-SiO2-TiO2 NCs demonstrated stable photocurrents 2.1 times higher than a bare carbon felt electrode and acetate production of 3.21 mM/d with a coulombic Efficiency of acetate 78% and a current density 2.7 A/m2, which was metabolized into acetate from HCO3- by cultivated anaerobic bacteria. The RGO-SiO2-TiO2 NCs-based supercapacitor achieved a maximum energy density of 35 Wh/kg at 630 W/kg power density, and after 10,000 cycles, it retained 84% capacitance stability at 10 A/g with 180 F/g at 1.25 A/g. This method presents a straightforward, cost-effective approach for mitigating CO2 emissions and generating energy harvesting devices. [Display omitted] •RGO-TiO2-SiO2 NCs offer the innovative potential for the energy and environmental crisis.•Photo-generated electrons accelerate transport rate and increase CO2 reduction.•Higher currents boost acetate production to 3.21 mM/d with 78% coulombic efficiency.•Device shows excellent cycle stability: 86% capacitance retained after 10,000 cycles.