Highly accessible surface area and heteroatom-doping are desired properties for carbon electrode materials to be used in electrochemical supercapacitors. In this paper, nitrogen and sulfur doped carbon materials with wide mesopores (13-14 nm) were synthetized according to a hard template approach by pyrolysis of sucrose, 1,10-phenanthroline or dibenzothiophene as carbon, nitrogen-carbon or sulfur-carbon precursors, respectively. The morphology and dimension of mesopores were induced by sacrificial SiO2 nanoparticles (10-20 nm), which are removed at the end of synthesis by an etching solution to reveal a network of hemispherical pores. The interconnected pore structure was confirmed by scanning electron microscopy and transmission electron microscopy. X-ray photoemission spectroscopy and elemental analysis confirmed the presence of nitrogen and sulfur functional groups. The prepared materials were fully characterized by cyclic voltammetry, chronopotentiometry and electrochemical impedance spectroscopy in 0.5 M H2SO4. Notwithstanding the small surface (200 m2g-1) determined by BET method, the nitrogen doped mesoporous carbon showed high specific gravimetric (∼170 F g-1) and surface (∼835 F m-2) capacitances that are comparable to those of materials with much higher surface area (5-10-fold higher).
Nitrogen and Sulfur Doped Mesoporous Carbons, Prepared from Templating Silica, as Interesting Material for Supercapacitors
BRANDIELE, RICCARDO;PICELLI, LUCA;PILOT, ROBERTINO;CAUSIN, VALERIO;MARTUCCI, ALESSANDRO;RIZZI, GIAN-ANDREA;AHMED ISSE, ABDIRISAK;DURANTE, CHRISTIAN
;GENNARO, ARMANDO
2017
Abstract
Highly accessible surface area and heteroatom-doping are desired properties for carbon electrode materials to be used in electrochemical supercapacitors. In this paper, nitrogen and sulfur doped carbon materials with wide mesopores (13-14 nm) were synthetized according to a hard template approach by pyrolysis of sucrose, 1,10-phenanthroline or dibenzothiophene as carbon, nitrogen-carbon or sulfur-carbon precursors, respectively. The morphology and dimension of mesopores were induced by sacrificial SiO2 nanoparticles (10-20 nm), which are removed at the end of synthesis by an etching solution to reveal a network of hemispherical pores. The interconnected pore structure was confirmed by scanning electron microscopy and transmission electron microscopy. X-ray photoemission spectroscopy and elemental analysis confirmed the presence of nitrogen and sulfur functional groups. The prepared materials were fully characterized by cyclic voltammetry, chronopotentiometry and electrochemical impedance spectroscopy in 0.5 M H2SO4. Notwithstanding the small surface (200 m2g-1) determined by BET method, the nitrogen doped mesoporous carbon showed high specific gravimetric (∼170 F g-1) and surface (∼835 F m-2) capacitances that are comparable to those of materials with much higher surface area (5-10-fold higher).Pubblicazioni consigliate
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