Accounting for the Quantum Capacitance of Graphite in Constant Potential Molecular Dynamics Simulations
arxiv(2024)
摘要
Molecular dynamics simulations at a constant electric potential are an
essential tool to study electrochemical processes, providing microscopic
information on the structural, thermodynamic, and dynamical properties. Despite
the numerous advances in the simulation of electrodes, they fail to accurately
represent the electronic structure of materials such as graphite. In this work,
we introduce a simple parameterization method that allows to tune the
metallicity of the electrode based on a quantum chemistry calculation of the
density of states. As a first illustration, we study the interface between
graphite electrodes and two different liquid electrolytes, an aqueous solution
of NaCl and a pure ionic liquid, at different applied potentials. We show that
the simulations reproduce qualitatively the experimentally-measured
capacitance; in particular, they yield a minimum of capacitance at the point of
zero charge, which is due to the quantum capacitance contribution. An analysis
of the structure of the adsorbed liquids allows to understand why the ionic
liquid displays a lower capacitance despite its large ionic concentration. In
addition to its relevance for the important class of carbonaceous electrodes,
this method can be applied to any electrode materials (e.g. 2D materials,
conducting polymers, etc), thus enabling molecular simulation studies of
complex electrochemical devices in the future.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要