Synthesis of diamond

Diamond is impressive because of its wide range of extreme properties. By most measures, diamond is ‘the biggest and best’: it is the hardest known material, has the lowest coefficient of thermal expansion, is chemically inert and wear resistant, offers low friction, has high thermal conductivity, and is electrically insulating and optically transparent from the ultraviolet to the far infrared. Diamond already finds use in many different applications including, of course, its use as a precious gem, but also as a heat sink, as an abrasive, and as inserts and/or wear-resistant coatings for cutting tools. Obviously, it is possible to envisage many other potential applications for diamond as an engineering material, but progress in implementing many such ideas has been hampered by the comparative scarcity of natural diamond. This paper reports on the progress of the long running quest for ways to synthesize diamond in the laboratory.