Graphene oxide, which is the chemical exfoliation product of graphite powders, is probably still the only 2D material that can be made reliably into single layer dispersions with large sizes and high yield. It has received renewed interests and its potential in many applications has been demonstrated. There are some conflicting results about the properties of graphene oxide. For example, in old literature, graphene oxide (back then known as graphite oxide) was often described as a flammable material. However, in recent works, graphene oxide was reported to be a flame retardant. In another example, graphene oxide films have been noted to be highly stable in water and this property has made their use in membrane applications in solution possible.