Basicity‐Engineered Graphite Fluoride Functionalization and Beyond: An Unusual Reaction between Ultraweak Nucleophile and Ultrastrong CF Bonds

Abstract

AbstractGraphite fluoride‐launched graphene functionalization has attracted increasing interest in recent years. Highly basic nucleophiles are normally employed for ultrastrong CF bonding. However, frequently, an appreciable majority of C–F units of graphite fluoride are reductively eliminated, leading to low functionalization degrees. It is hypothesized that graphite fluoride could likely be functionalized to a larger degree by lowering the basicity of the nucleophiles. Herein, ultraweakly basic NH3·H2O is adopted as a nucleophile to react with extremely inert graphite fluoride, and the resulting reaction affords amino/hydroxyl cofunctionalized graphene (NH2–G–OH). As expected, the NH2/OH functionalization degree and the ratio of substituted C–F units to reduced ones reach high values of 0.34 and 1.62, respectively. Due to the dual energy‐storage mechanisms of the electrochemical double‐layer capacitance coupled with Faradaic pseudocapacitance, the NH2–G8–OH‐based all‐solid‐state supercapacitors are flexible and robust and deliver state‐of‐the‐art capacitive characteristics, while exhibiting high rate capability and electrochemical cycling stability. In addition, NH2/OH moieties remain highly reactive to be post‐functionalized by versatile electrophiles, not only achieving an umpolung of graphite fluoride, but also enabling NH2–G8–OH a competitive alternative to monopolistic GO, and opening up an innovative pathway for development of high‐performance graphene derivatives amenable to multifarious applications.