Cell-Membrane Inspired Multifunctional Nanocoating for Rescuing the Active-Material Microenvironment in High-Capacity Sulfur Cathode

Achieving healthy active-material microenvironment (ME@AM) for stable and efficient electron/ion transport around each active-material particle is crucial for high-performance battery electrodes. However, this goal has been proved extremely challenging for most high-capacity AMs such as sulfur, owing to its notable volume change and severe shuttle effect. Here, a multifunctional hybrid material with zein protein reinforced catalytic single Cu atom/carbon composite (Cu-C) (zein/Cu-C) is coated onto sulfur/carbon (SC) particle, to prepare the advanced zein/Cu-C@SC core-shell particle. Similar to the multifunctional cell membrane well-known in biology, this multifunctional zein/Cu-C coating helps build a healthy and stable ME@AM within sulfur cathode. Specifically, it can simultaneously provide robust protective shell for the AM particle, adsorption and catalyst function to the dissolved polysulfides, and AM surface treatment to improve AM/conductive agent interface. All these functions are the keys to build and maintain a healthy ME@AM in sulfur cathode. This study not only brings effective solutions to the challenges in volume-change high-capacity sulfur active materials and beyond, but also helps achieve comprehensive understanding of the key factors controlling the structuring and final quality of ME@AM.