Self‐Propagating Domino‐like Reactions in Oxidized Graphite

Abstract

Graphite oxide (GO) has received extensive interest as a precursor for the bulk production of graphene‐based materials. Here, the highly energetic nature of GO, noted from the self‐propagating thermal deoxygenating reaction observed in solid state, is explored. Although the resulting graphene product is quite stable against combustion even in a natural gas flame, its thermal stability is significantly reduced when contaminated with potassium salt by‐products left from GO synthesis. In particular, the contaminated GO becomes highly flammable. A gentle touch with a hot soldering iron can trigger violent, catastrophic, total combustion of such GO films, which poses a serious fire hazard. This highlights the need for efficient sample purification methods. Typically, purification of GO is hindered by its tendency to gelate as the pH value increases during rinsing. A two‐step, acid–acetone washing procedure is found to be effective for suppressing gelation and thus facilitating purification. Salt‐induced flammability is alarming for the fire safety of large‐scale manufacturing, processing, and storage of GO materials. However, the energy released from the deoxygenation of GO can also be harnessed to drive new reactions for creating graphene‐based hybrid materials. Through such domino‐like reactions, graphene sheets decorated with metal and metal oxide particles are synthesized using GO as the in situ power source. Enhanced electrochemical capacitance is observed for graphene sheets loaded with RuO2 nanoparticles.

Fabrication of Ce-doped MnO2decorated graphene sheets for fire safety applications of epoxy composites: flame retardancy, smoke suppression and mechanism

“…[4][5][6] Very recently, similar to some other members of the family of carbon-based materials, such as expanded graphite, graphite oxide and carbon nanotubes, graphene has attracted interests in scientific field as a flame retardant additive. 7,8 Kim et al 9 demonstrated that graphene is actually thermally stable even after exposing it to a flame, clearly indicating the high intrinsic flame resistance of graphene. In addition, there are some other reports regarding the application of graphene as a flame retardant additive in polymer composites.…”

Mechanical Properties, Thermal Stability, and Glass Transition Behaviors of a Waterborne Polyurethane/Graphene Oxide Nanocomposite

“…Weight loss at the rst stage is accelerated by the incorporation of GO nanosheets as can be seen in TGA and DTA results. Increased heat transfer due to the high thermal conductivity of GO or potassium salt impurities in GO 24) may be the cause of the promoted thermal degradation at lower temperature. However, the weight loss at the second stage is retarded to higher temperature by the GO nanosheets.…”

Water Processable Graphene Oxide:Single Walled Carbon Nanotube Composite as Anode Modifier for Polymer Solar Cells

“…[ 22 ] The purifi ed GO, with typical lateral size of a few microns, was dried and redispersed in deionized water to create dispersions. SWCNTs were …”

“…Since GO can undergo partial deoxygenation upon gentle heating, [ 22 ] further work is also needed to evaluate the long term stability of devices with GO based modifying layers.…”