본문 바로가기
  • Home

Effects of supercritical-CO2 treatment on the pore structure and H2 adsorptivity of single-walled carbon nanohorns

  • Carbon Letters
  • Abbr : Carbon Lett.
  • 2024, 34(9), pp.2317-2323
  • DOI : 10.1007/s42823-024-00757-7
  • Publisher : Korean Carbon Society
  • Research Area : Natural Science > Natural Science General > Other Natural Sciences General
  • Received : May 17, 2024
  • Accepted : May 28, 2024
  • Published : December 5, 2024

Kim Nam Ryeol 1 Wee Jae-Hyung 1 Kim Chang Hyo 2 Kim Dong Young 3 Kaneko Katsumi 4 Yang Cheol-Min 1

1한국과학기술연구원
2한국화학연구원
3한국탄소산업진흥원
4독립연구자

Accredited

ABSTRACT

We investigated the effects of supercritical-CO2 treatment on the pore structure and consequent H2 adsorption behavior of single-walled carbon nanohorns (SWCNHs) and SWCNH aggregates. High-resolution transmission electron microscopy and adsorption characterization techniques were employed to elucidate the alterations in the SWCNH morphology and aggregate pore characteristics induced by supercritical-CO2 treatment. Our results confirm that supercritical-CO2 treatment reduces the interstitial pore surface area and volume of SWCNH aggregates, notably affecting the adsorption of N2 (77 K), CO2 (273 K), and H2 (77 K) gasses. The interstitial porosity strongly depends on the supercritical-CO2 pressure. Supercritical-CO2 treatment softens the individual SWCNHs and opens the core of SWCNH aggregates, producing a partially orientated structure with interstitial ultramicropores. These nanopores are formed by the diffusion and intercalation of CO2 molecules during treatment. An increase in the amount of H2 adsorbed per interstitial micropore of the supercritically modified SWCNHs was observed. Moreover, the increase in the number and volume of ultramicropores enable the selective adsorption of H2 and CO2 molecules. This study reveals that supercritical-CO2 treatment can modulate the pore structure of SWCNH aggregates and provides an effective strategy for tailoring the H2 adsorption properties of nanomaterials.

Citation status

* References for papers published after 2023 are currently being built.