Hydrothermally Carbonized Waste Biomass as Electrocatalyst Support for α-MnO2 in Oxygen Reduction Reaction

Catalysts

EugeneA. Esparcia¹  JulieAnne D. del Rosario¹  JoeyD. Ocon¹  JethroDaniel A. Pascasio¹  HaroldO. Panganoron¹ 

[1] Laboratory of Electrochemical Engineering, Department of Chemical Engineering, College of Engineering, University of the Philippines, Diliman, Quezon City 1101, Philippines;

关键词: hydrothermal carbonization;    biomass;    hydrochar;    activated carbon;    mno₂/c;    oxygen reduction reaction;   

DOI  :  10.3390/catal10020177

来源: DOAJ

【 摘 要 】

Sluggish kinetics in oxygen reduction reaction (ORR) requires low-cost and highly durable electrocatalysts ideally produced from facile methods. In this work, we explored the conversion and utilization of waste biomass as potential carbon support for α-MnO₂ catalyst in enhancing its ORR performance. Carbon supports were derived from different waste biomass via hydrothermal carbonization (HTC) at different temperature and duration, followed by KOH activation and subsequent heat treatment. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX) and X-Ray diffraction (XRD) were used for morphological, chemical, and structural characterization, which revealed porous and amorphous carbon supports for α-MnO₂. Electrochemical studies on ORR activity suggest that carbon-supported α-MnO₂ derived from HTC of corncobs at 250 °C for 12 h (CCAC + MnO₂ 250-12) gives the highest limiting current density and lowest overpotential among the synthesized carbon-supported catalysts. Moreover, CCAC + MnO₂ 250-12 facilitates ORR through a 4-e^‑ pathway, and exhibits higher stability compared to VC + MnO₂ (Vulcan XC-72) and 20% Pt/C. The synthesis conditions preserve oxygen functional groups and form porous structures in corncobs, which resulted in a highly stable catalyst. Thus, this work provides a new and cost-effective method of deriving carbon support from biomass that can enhance the activity of α-MnO₂ towards ORR.

【 授权许可】

Unknown