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

Abstract 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.