Logo image
Back
Small-angle neutron scattering characterization of the structure of nanoporous carbons for energy-related applications
Journal article   Peer reviewed

Small-angle neutron scattering characterization of the structure of nanoporous carbons for energy-related applications

Lilin He, Suresh M Chathoth, Yuri B Melnichenko, Volker Presser, John McDonough and Yury Gogotsi
Microporous and mesoporous materials, v 149(1), pp 46-54
2012
DOI: https://doi.org/10.1016/j.micromeso.2011.08.035
Featured in Collection :   UN Sustainable Development Goals @ Drexel

Abstract

Sorption Carbide-derived porous carbon Structure SANS
[Display omitted] ► We studied the structure of porous carbide-derived carbon. ► Samples were obtained at four different chlorination temperatures T Cl. ► SANS indicates a crossover from nearly spherical to elongated pores as T Cl increases. ► SANS results agree with gas adsorption measurements at high T Cl. ► For lower T Cl, pore radii obtained from gas sorption are overestimated. We used small-angle neutron scattering (SANS) and neutron contrast variation to study the structure of four nanoporous carbons prepared by thermo-chemical etching of titanium carbide TiC in chlorine at 300, 400, 600, and 800 °C with pore diameters ranging between ∼4 and ∼11 Å. SANS patterns were obtained from dry samples and samples saturated with deuterium oxide (D 2O) in order to delineate origin of the power law scattering in the low Q domain as well as to evaluate pore accessibility for D 2O molecules. SANS cross section of all samples was fitted to Debye–Anderson–Brumberger (DAB), DAB–Kirste–Porod models as well as to the Guinier and modified Guinier formulae for cylindrical objects, which allowed for evaluating the radii of gyration as well as the radii and lengths of the pores under cylindrical shape approximation. SANS data from D 2O-saturated samples indicate that strong upturn in the low Q limit usually observed in the scattering patterns from microporous carbon powders is due to the scattering from outer surface of the powder particles. Micropores are only partially filled with D 2O molecules due to geometrical constraints and or partial hydrophobicity of the carbon matrix. Structural parameters of the dry carbons obtained using SANS are compared with the results of the gas sorption measurements and the values agree for carbide-derived carbons (CDCs) obtained at high chlorination temperatures (>600 °C). For lower chlorination temperatures, pore radii obtained from gas sorption overestimate the actual pore size as calculated from SANS for two reasons: inaccessible small pores are present and the model-dependent fitting based on density functional theory models assumes non-spherical pores, whereas SANS clearly indicates that the pore shape in microporous CDC obtained at low chlorination temperatures is nearly spherical.

Metrics

15 Record Views
39 citations in Web of Science
42 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#11 Sustainable Cities and Communities

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Collaboration types
Domestic collaboration
Web of Science research areas
Chemistry, Applied
Chemistry, Physical
Materials Science, Multidisciplinary
Nanoscience & Nanotechnology
Logo image