Synthesis of Mesoporous Carbons with Controllable N-Content and Their Supercapacitor Properties

Abstract

A synthesis route to ordered mesoporous carbons with controllable nitrogen content has been developed for high-performance EDLC electrodes. Nitrogen-doped ordered mesoporous carbons (denoted as NMC) were prepared by carbonizing a mixture of two different carbon sources within the mesoporous silica designated by KIT-6. Furfuryl alcohol was used as a primary carbon precursor, and melamine as a nitrogen dopant. This synthesis procedure gave cubic Ia3d mesoporous carbons containing nitrogen as much as 13%. The carbon exhibited a narrow pore size distribution centered at 3-4 nm with large pore volume (0.6-1 cm 3 g −1) and high specific BET surface area (700-1000 m 2 g −1). Electrochemical behaviors of the NMC samples with various Ncontents were investigated by a two-electrode measurement system at aqueous solutions. At low current density, the NMC exhibited markedly increasing capacitance due to the increase in the nitrogen content. This result could be attributed to the enhanced surface affinity between carbon electrode and electrolyte ions due to the hydrophilic nitrogen functional groups. At high current density conditions, the NMC samples exhibited decreasing specific capacitance against the increase in the nitrogen content. The loss of the capacitance with the N-content may be explained by high electric resistance which causes a significant IR drop at high current densities. The present results indicate that the optimal nitrogen content is required for achieving high power and high energy density simultaneously.

Energy-Dense Aqueous Carbon/Carbon Supercapacitor with a Wide Voltage Window

“…The loss of specific capacitance of the sym-GFAC-800 SC at higher current density may be explained by its high internal resistance, which causes a significant IR drop of 0.23 V at 10 A g −1 . 49 The IR drops observed for the sym-GFAC-800 SC during the GCD studies are comparable to the reported literature. 25,47,50 The energy density of the sym-GFAC-800 SC is compared with recent aqueous carbon-based high voltage SCs (Table SI).…”

S, N and Cl Separately Doped Graphene Oxide/Polyaniline Composites for Hybrid Supercapacitor Electrode

“…In addition, increasing the quantity of -N generally accelerates the active material's redox process. 46 The amount of N1s might have increased as a result of the strong π-π interaction between the PANI backbone and Cl-GO. 47,48 Furthermore, with the doping of Cl-GO, chlorine-containing oxygenated functional groups and higher electronegativity of chlorine atom compared to other heteroatoms (-S and -N), may have supported the formation of quinoid amine (=N-), secondary amine structure (-NH-) and positively charged nitrogen (-N+-) structures formed by polymerization reaction in PANI structure (Fig.…”

Doping strategy, properties and application of heteroatom-doped ordered mesoporous carbon

“…The original researches led by Ryoo developed a N-doped OMC for electric double layer capacitor (EDLC) electrodes in 2008. 124 In the pioneering studies, the SSA of N-doped OMC and the corresponding specific capacitance were not perfect. 124,125 The largest SSA of N-doped OMC by Ryoo and Kim et al were only 778 and 725 m 2 g −1 , respectively.…”

“… 124 In the pioneering studies, the SSA of N-doped OMC and the corresponding specific capacitance were not perfect. 124,125 The largest SSA of N-doped OMC by Ryoo and Kim et al were only 778 and 725 m 2 g −1 , respectively. The highest capacitance of the electrodes was 182 F g −1 at 10 mV s −1 , which was higher than that of pure OMC (147 F g −1 ).…”