Self-assembled molecular nanocathodes for rechargeable energy storage modules

Abstract

We demonstrate the proof-of-concept of using self-assembled monolayers (SAMs) as nanocathodes for rechargeable Li ion batteries. Potential advantages of SAM nanocathodes include high surface area, high power-weight ratios, facile fabrication, and repair through molecular desorption and reassembly. Nanocathodes comprised of diphenyl disulfide SAMs formed on gold surfaces were characterized by cyclic voltammetry, impedance spectroscopy, infrared spectroscopy and X-ray photoelectron spectroscopy. Our results show that charging and discharging involve Li⁺ ion release and capture, respectively, via nanocrevices in the SAMs. Li⁺-ion entrapment in the SAMs via interaction with π -electrons and sulfur decrease battery lifetime upon repeated charging and discharging.