Almost ready for do it yourself at home? (just kidding) This could be a game changer!
"Diamonds have been synthesised at atmospheric pressure by researchers in South Korea. The researchers do not yet fully understand the underlying mechanism that forms these diamond films, but it involves passing methane over liquid gallium. They are working, however, to optimise the synthesis to produce higher-quality diamonds that they hope could find a range of uses. ..."
From the abstract:
"Natural diamonds were (and are) formed (thousands of million years ago) in the upper mantle of Earth in metallic melts at temperatures of 900–1,400 °C and at pressures of 5–6 GPa. Diamond is thermodynamically stable under high-pressure and high-temperature conditions as per the phase diagram of carbon. Scientists at General Electric invented and used a high-pressure and high-temperature apparatus in 1955 to synthesize diamonds by using molten iron sulfide at about 7 GPa and 1,600 °C. There is an existing model that diamond can be grown using liquid metals only at both high pressure and high temperature. Here we describe the growth of diamond crystals and polycrystalline diamond films with no seed particles using liquid metal but at 1 atm pressure and at 1,025 °C, breaking this pattern. Diamond grew in the subsurface of liquid metal composed of gallium, iron, nickel and silicon, by catalytic activation of methane and diffusion of carbon atoms into and within the subsurface regions. We found that the supersaturation of carbon in the liquid metal subsurface leads to the nucleation and growth of diamonds, with Si playing an important part in stabilizing tetravalently bonded carbon clusters that play a part in nucleation. Growth of (metastable) diamond in liquid metal at moderate temperature and 1 atm pressure opens many possibilities for further basic science studies and for the scaling of this type of growth."
Making Diamonds at Ambient Pressure (original news release) - Scientists develop novel liquid metal alloy system to synthesize diamond under moderate conditions -
Growth of diamond in liquid metal at 1 atm pressure (no public access)
Figure 1. Growth of diamond in liquid metal alloy under 1 atmosphere pressure.
Diamond can be grown on this metal substrate by passing methane over it when it is liquid
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