Molecular Langmuir–Blodgett Film for Silicon Anode Interface Engineering

Abstract

Silicon-based anodes are widely expected to vastly improve the performance of lithium-ion batteries (LIBs). However, the silicon anode interface is well-known to be unstable and reactive, leading to various electrolyte side reactions that would ultimately lower the battery performance. Consequently, it is critically important to rationally design the silicon anode to stabilize its interface. The Langmuir–Blodgett (LB) technique is a well-established, versatile, and powerful method for fabricating ultrathin films over solid substrates. Here, we utilize LB approach to generate thin films composed of small organic molecules over silicon electrodes as protective layers. Such molecular layers were found capable of mediating the electrochemical behavior of silicon electrodes in both aqueous and organic carbonate electrolytes. This study illustrates the applicability of small-molecule LB films in electrode interface engineering for LIB technology development.