Abstracts Book - IMRC 2018

• SA1-O017 Invited Talk
ATOMISTIC SIMULATIONS OF ORDERED AND DISORDERED
CARBONS: “MIMICKING” , “TARGETING” AND “IMAGING”
Roland Pellenq 1,2
1 CNRS, MSE2 / CNRS-MIT-AMU, France. 2 Massachusetts Institute of Technology, MITEI / CEE,
United States.
Atomistic simulation techniques have become extremely valuable tools for the
elucidation of the structure of disordered or (partially) ordered materials. These
techniques not only allow for the production of large-scale three-dimensional
representations of the materials from the atomic scale, but also to predict most
of their properties, and in some cases, to assess their formation mechanisms.
In this talk, I will focus on carbon materials that can be ordered as well as
disordered. There two routes to obtain realistic molecular-scale reconstruction
of porous carbons: mimicking their formation process and targeting a “final”
state by constraining/guiding the simulation using experimental texture
information. Obviously the first is a priori more predictive than the second but
requires dealing upfront with chemistry (through reactive force fields) than can
be rather complex with kinetically hindered processes. To illustrate the
mimicking route, I will present (i) the Grand-Canonical numerical synthesis of
ordered carbon phases by carbon vapor deposition on zeolites and MCM-type
mesoporous oxides, (ii) the Replica Exchange MD simulation of the geological
degradation of the main components of wood (lignin, cellulose and fatty acids)
into disordered nanoporous carbons and kerogen phases with the production
of a complex liquid phase. The so-called targeting route will be illustrated with
the example of the kerogen phases using the Hybrid-Reverse Monte-Carlo
approach with an extension towards their mechanical properties from elasticity
to failure (fracture). Finally, I will present new electron-tomography 3D images
with sub-nanometric resolution that allow structural characterization of
disordered organic porous networks as well as mechanical and confined fluid
transport properties to be derived in a consistent manner including knowledge
that was gained from atomistic simulations. Applied to kerogen phases, the
results of this unprecedented approach evidenced i) increasingly tortuous and
connected pore networks with respect to thermal maturity, ii) the crucial effect
of topology and adsorbed fluids on the mechanical behavior, and iii) the
dominant impact of diffusion mechanisms occurring within the nanoporosity on
hydrocarbon transport at the mesoscale.