Oxidative-polymerization and deoxygenation of mixed phenols to faradaic-oxygen modified mesoporous carbon and its

To find the effect of phenols type on the physical/chemical characteristics and their supercapacitor performances of the derived carbons. Herein, three types of diphenol isomers (catechol, resorcinol and hydroquinone) mixed with phenol (molar ratio of 1:1) were employed as precursors to prepared porous carbon by oxidation polymerization and deoxygenation method. Systematically investigation shows that the derived three carbons all ahcieves a disordered mesoporous structure, while, hydroquinone mixed with phenol derived carbon (HPMC973) owns higher surface area of 1758 m(2)/g than that of catechol mixed with phenol derived CPMC973 of 1303 m(2)/g and resorcinol mixed with phenol derived RPMC973 of 1452 m(2)/g, larger pore volume of 1.94 cm(3)/g (vs. CPMC973 of 1.09 and RPMC973 of 1.25 cm(3)/g) and more open structure with larger mesoporosity of 97.3% vs. CPMC973 (86.1%) and RPMC973 (96.1%) resulted from its unique spatial structure enabling the formation of highly cross-linked structure. The residual oxygen species in the three carbons mainly exist in the forms of -C = O and -COO-. Benefited from the highly open-accessed mesoporosity and rich electroactive oxygenic species, the HPMC973 electrode exhibits a high capacitance of 418 F/g@0.5 A/g (vs 306 F/g for CPMC973 and 302 F/g for RPMC973) in 1.0 M H2SO4, the capacitance can be maintianed at 325 F/g@20 A/g, showing a superior rate capability with the retention of 77.8%. The fabricated symmetric supercapacitor based on HPMC973 in 1.0 M Li2SO4 delivers a ultrahigh specific energy of 27.9 Wh/kg@895 W/kg (vs. 16.9 Wh/kg for RPMC973 and 15.8 Wh/kg for CPMC973) and achieves an excellent cycling stablity with near 100% capacitance retention after 10 000 cylces at large current density of 20 A/g, offering a great potential for energy storage application. The current research provides a facile method for the fabrication of mesoporous carbon without using the harmful formaldehyde thus affords a promissing candidate for wide application in sorption, catalysis, energy storage, and etc.

Automated summary

The study investigated the effects of different phenols on the physical/chemical characteristics and supercapacitor performances of derived carbons. Hydroquinone mixed with phenol derived carbon exhibited higher surface area, larger pore volume, and more open structure, resulting in superior capacitance and rate capability. The research provides a facile method for fabricating mesoporous carbon with potential applications in energy storage and other fields.