TY - JOUR

T1 - Optimizing surfactant removal from a soft-templated ordered mesoporous carbon precursor: an in situ SAXS study

AU - Rauscher, Max

AU - Seyffertitz, Malina

AU - Kohns, Richard

AU - Stock, Sebastian

AU - Amenitsch, Heinz

AU - Huesing, Nicola

AU - Paris, Oskar

PY - 2023/5/2

Y1 - 2023/5/2

N2 - In situ small-angle X-ray scattering (SAXS) was employed to identify critical parameters during thermal treatment for template removal of an ordered mesoporous carbon precursor synthesized via a direct soft-templating route. The structural parameters obtained from the SAXS data as a function of time were the lattice parameter of the 2D hexagonal structure, the diameter of the cylindrical mesostructures and a power-law exponent characterizing the interface roughness. Moreover, detailed information on contrast changes and pore lattice order was obtained from analysis of the integrated SAXS intensity of the Bragg and diffuse scattering separately. Five characteristic regions during heat treatment were identified and discussed regarding the underlying dominant processes. The influence of temperature and O2/N2 ratio on the final structure was analyzed, and parameter ranges were identified for an optimized template removal without strongly affecting the matrix. The results indicate that the final structure and controllability of the process are optimum for temperatures between 260 and 300°C with a gas flow containing 2 mol% of O2.

AB - In situ small-angle X-ray scattering (SAXS) was employed to identify critical parameters during thermal treatment for template removal of an ordered mesoporous carbon precursor synthesized via a direct soft-templating route. The structural parameters obtained from the SAXS data as a function of time were the lattice parameter of the 2D hexagonal structure, the diameter of the cylindrical mesostructures and a power-law exponent characterizing the interface roughness. Moreover, detailed information on contrast changes and pore lattice order was obtained from analysis of the integrated SAXS intensity of the Bragg and diffuse scattering separately. Five characteristic regions during heat treatment were identified and discussed regarding the underlying dominant processes. The influence of temperature and O2/N2 ratio on the final structure was analyzed, and parameter ranges were identified for an optimized template removal without strongly affecting the matrix. The results indicate that the final structure and controllability of the process are optimum for temperatures between 260 and 300°C with a gas flow containing 2 mol% of O2.

KW - SAXS

KW - In Situ Behandlung

KW - carbon

KW - Mesoporous carbon

KW - calcination

KW - ordered mesoporous carbon

U2 - 10.1107/S1600576723003886

DO - 10.1107/S1600576723003886

M3 - Article

VL - 56.2023

SP - 801

EP - 809

JO - Journal of applied crystallography

JF - Journal of applied crystallography

SN - 1600-5767

IS - 3

ER -