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

Abstract

Graphite 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 NH 3 ·H 2 O is adopted as a nucleophile to react with extremely inert graphite fluoride, and the resulting reaction affords amino/hydroxyl cofunctionalized graphene (NH 2 -G-OH). As expected, the NH 2 /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 NH 2 -G 8 -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, NH 2 /OH moieties remain highly reactive to be post-functionalized by versatile electrophiles, not only achieving an umpolung of graphite fluoride, but also enabling NH 2 -G 8 -OH a competitive alternative to monopolistic GO, and opening up an innovative pathway for development of high-performance graphene derivatives amenable to multifarious applications.

Graphene Acid for Lithium‐Ion Batteries—Carboxylation Boosts Storage Capacity in Graphene

“…[43] More details on the chemistry of fluorographene can also be found in other works. [49][50][51] In the following step, a relatively mild acidic hydrolysis selectively transformed the CN covalent functionalities to COOH, yielding GA. [43] This particular methodology bypasses the harsh oxidation conditions used to introduce diverse oxygen-containing functional groups to graphene during a GO synthesis, and contributed to GA's conductivity, as revealed by conductivity measurements, cyclic voltammetry (CV), electrochemical impendance spectroscopy (EIS), and density functional theory (DFT) calculations. [43] GA electrodes (mixed with Ketjenblack EC-600JD as a conductive additive and polymer binder at a 90:5:5 mass ratio and cast onto a copper current collector) were evaluated in coin cells versus Li metal (Experimental Section).…”

Regulating the Bonding Nature and Location of C–F Bonds in Fluorinated Graphene by Doping Nitrogen Atoms

“…Traditionally, for reported F/N bifunctional graphene derivatives, only fluorine content or nitrogen content is possible to get a high value, while highly F/N-difunctionalized graphene derivatives have not been reported ,− (Figure a). Here, this method makes it possible to prepare bifunctional graphene with a high content of N and high content of F. Based on the effect of doped N atoms on fluorination reaction, ultrahighly functionalized fluorinated N-doped graphene (UH-FNG) with superhigh content of N and F (Figure b) has been obtained here by adjusting the concentration of fluorine.…”

NaCl-Assisted Ultrasmall Mo2C Nanocrystals Confined in N, S Double-Doped Hierarchical Porous Carbon for Efficient Hydrogen Generation

“…Accordingly, the chemical signals related to N, S, and Mo functional groups were detected by FTIR spectroscopy. As presented in Figure S14, the peak between 3200 and 3700 cm −1 is attributed to the stretching vibration of the O−H or N−H bonds, 37 and the peak at 1643 cm −1 is assigned to the NC or CC double bonds. 38 In addition, the transmission peak between 1000 and 1225 cm −1 is caused by the absorption of C−O or C−S bonds, and the peak between 690 and 870 cm −1 is related to the stretching vibration of Mo−C or Mo−O bonds.…”