 Emzines have gained much attention since their discovery in 2011 due to their unique properties such as high conductivity, low ion diffusion barriers, rich surface chemistry, and excellent mechanical strength. However, two major obstacles hinder their widespread use, the high risk of preparation methods like hydrofluoric acid, HF, etching, and the difficulty in obtaining emzines with controlled surface groups. Recent research on Lewis acidic etching has shown promise in addressing these problems, as it is safer than traditional etching methods and can be used to control the surface termination of emzines. This review discusses the mechanisms behind Lewis acidic etching, how it can be used to regulate the surface termination of emzines, and its potential applications in energy storage and conversion, sensors, and microwave absorption. Additionally, the challenges and opportunities associated with this technique are discussed. This article was authored by Pengfei Huang and Wei Chonghan.