History and Preparation
Graphite oxide was first prepared by Oxford chemist Benjamin C. Brodie in 1859, by treating graphite with a mixture of potassium chlorate and fuming nitric acid. In 1957 Hummers and Offeman developed a safer, quicker, and more efficient process, using a mixture of sulfuric acid H2SO4, sodium nitrate NaNO3, and potassium permanganate KMnO4, which is still widely used (as of 2009).
Recently a mixture of H2SO4 and KMnO4 has been used to cut open carbon nanotubes lengthwise, resulting in microscopic flat ribbons of graphene, a few atoms wide, with the edges "capped" by oxygen atoms (=O) or hydroxyl groups (-OH).
Graphite oxide has also been prepared by using a "bottom-up" synthesis method (Tang-Lau method) in which the sole source is glucose, the process is safer, more easy, and more environmentally friendly compared to traditionally “top-down” method, in which strong oxidizers must be involved. Another important advantage of Tang-Lau method is thickness controllable ranging from monolayer to multilayers by simply adjusting growth parameters.
Read more about this topic: Graphite Oxide
Famous quotes containing the words history and/or preparation:
“The history of American politics is littered with bodies of people who took so pure a position that they had no clout at all.”
—Ben C. Bradlee (b. 1921)
“Living each day as a preparation for the next is an exciting way to live. Looking forward to something is much more fun than looking back at something—and much more constructive. If we can prepare ourselves so that we never have to think, “Oh, if I had only known, if I had only been ready,” our lives can really be the great adventure we so passionately want them to be.”
—Hortense Odlum (1892–?)