Highly ordered iron oxide-mesoporous fullerene nanocomposites for oxygen reduction reaction and supercapacitor applications

• DOI: 10.1016/j.micromeso.2019.04.071
• Publication Date: 2019-05-01T01:40:57Z
• Authors: Mercy R. Benzigar; Stalin Joseph; Gopalan Saianand; Anantha-Iyengar G...; Sujoy Sarkar; Sampath Srinivasan; Dae-Hwan Park; Sungho Kim; Siddulu Naidu Tal...; Kavitha Ramadass; Ajayan Vinu
• Keywords: mesoporous carbon; nanoporous carbon; nanotemplating; mesoporous silica; 02 engineering and technology; 540; 0210 nano-technology; Inorganic & Physical Chemistry; energy

Abstract In this study, we report a facile synthetic strategy to embed ultra-small iron oxide nanoparticles within the channels of highly ordered mesoporous fullerene (C60) (Fe-MFC60-T, where T denotes the temperature of the template synthesis). The present work is judicially designed to form the hematite phase of iron oxide (α-Fe2O3) nanoparticles (NPs) through the subsequent calcination of Fe-MFC60-T. The Fe-MFC60-T materials were analysed comprehensively for obtaining their physico-chemical properties. Among the materials studied, Fe-MFC60-150 exhibits a unique doughnut-shaped morphology with a high specific surface area (∼598 m2 g−1), crystalline wall structure, and well-ordered porosity. The Fe-MFC60-150 displays an adequate oxygen reduction reaction (ORR) activity with a positive onset potential at 0.85 V (vs RHE) and half wave potential at 0.78 V (vs RHE), low Tafel slope (66 mV per decade), high exchange current density (1.2 × 10−10 A cm−2), and good tolerance towards methanol crossover. We also demonstrate that Fe-MFC60-150 is capable of delivering a specific capacitance of 112.4 F g−1 at 0.1 A g−1. The electrochemical performance of Fe-MFC60-150 towards ORR and supercapacitor can be ascribed to the synergistic coupling effects between the active sites of α-Fe2O3 and MFC60.