Kim, YT Ito, Y Tadai, K Mitani, T Kim, US Kim, HS Cho, BW 2024-01-21T04:01:42Z 2024-01-21T04:01:42Z 2021-09-02 2005-12-05 0003-6951 https://pubs.kist.re.kr/handle/201004/135895 In this letter we show that it is possible to drastically change electric double layer capacitance, from a large increase to complete disappearance, by introducing various surface functional groups on carbon nanotubes. The introduction of surface carboxyl groups created a 3.2 times larger capacitance due to the increased hydrophilicity of the multiwalled carbon nanotubes in an aqueous electrolyte. In contrast, the introduction of alkyl groups resulted in a marked decrease of capacitance. Notably, we unexpectedly observed the complete disappearance of capacitance for samples functionalized with longer alkyl groups than octyl, indicating the perfect block of proton access to the carbon nanotubes' surfaces by extreme hydrophobicity. (c) 2005 Americian Institute of Physics. English AMER INST PHYSICS ACTIVATED CARBON SUPERCAPACITORS Drastic change of electric double layer capacitance by surface functionalization of carbon nanotubes Article 10.1063/1.2139839 1 APPLIED PHYSICS LETTERS, v.87, no.23 APPLIED PHYSICS LETTERS 87 23 scie scopus 000233723200100 2-s2.0-28444453273 Physics, Applied Physics Article ACTIVATED CARBON SUPERCAPACITORS capacitor surface funtionalization carbon nanotube electric double layer