ChemInform Abstract: High‐Level Doping of Nitrogen, Phosphorus, and Sulfur into Activated Carbon Monoliths and Their Electrochemical Capacitances.

Abstract

High-Level Doping of Nitrogen, Phosphorus, and Sulfur into Activated CarbonMonoliths and Their Electrochemical Capacitances. -Activated carbon monoliths prepared from resorcinol-formaldehyde gels by carbonization (1000 C, 2 h) under N 2 and CO2 are doped by N using urea, a mixture of NaNH2 and NH4Cl, or hexamethylenetetramine, by red P, and by S using a mixture of Na 2S2O5 and Na2S2O7 whereby the activated carbon and the dopant are separated from each other within the reaction tubes (Pyrex or quartz tubes, 1. 600-1000 C, 2 h, 2. vacuum annealing, 300 C, 12 h). In addition, sequential doping reactions give rise to dual-and triple--heteroatom-doped carbons. The pore properties of the precursor C are preserved through each doping process. Electrochemical investigations of undoped and doped carbon monolithic supercapacitor electrodes reveal an improved surface to electrolyte compatibility for doped electrodes. -(HASEGAWA*, G.; DEGUCHI, T.; KANAMORI, K.; KOBAYASHI, Y.; KAGEYAMA, H.; ABE, T.; NAKANISHI, K.; Chem. Mater. 27 (2015) 13, 4703-4712, http://dx.doi.org/10.1021/acs.chemmater.5b01349 ; Dep. Energy Hydrocarbon Chem., Grad. Sch. Eng., Kyoto Univ., Nishikyo, Kyoto 615, Japan; Eng.) -J. Schramke 38-008

Cooperation of nitrogen-doping and catalysis to improve the Li-ion storage performance of lignin-based hard carbon

“…Three samples have relative low R s ( < 5 ). CLM-Ni has lower R f (35 ) and R ct (18 ) than those of CLM ( R f : 43 ; R ct : 33 ) and CL ( R f : 67 ; R ct : 86 ). CLM-Ni possesses the lowest R ct indicating the highest rate capability among as-prepared samples.…”

“…CLM-Ni displays much better rate capability due to the cooperation of nitrogen-doping and catalysis. Graphitic nitrogen and pyridine nitrogen in carbon matrix are positively charged, which make for electrons transferring through the carbon, improving the electrochemical performance at high rates [35] . Additionally, the graphitic structure generated by catalysis could also improve the electrical conductivity of hard carbon.…”