Researchers at the Institute for Basic Science in South Korea have developed an innovative method to create diamonds at normal atmospheric pressure without a starter gem. Remarkably, this new process takes just 15 minutes, potentially transforming the diamond industry.
How Natural Diamonds Form
Diamonds naturally form deep within the Earth’s mantle under extreme conditions, involving immense pressures and temperatures above 2,700 degrees Fahrenheit (1,500 degrees Celsius). This natural process spans millions of years, making diamonds highly valued and rare.
Conventional Methods of Creating Artificial Diamonds
Traditionally, most synthetic diamonds are produced using the high-pressure, high-temperature (HPHT) method. This technique replicates the natural diamond-forming environment by subjecting carbon to intense pressure and heat, often around a small seed diamond. While effective, HPHT is energy-intensive and requires starter diamonds.
A Breakthrough in Diamond Synthesis
Rodney Ruoff, a physical chemist at the Institute for Basic Science, and his research team have introduced a new method that circumvents the limitations of traditional techniques. Their research, published in Nature, outlines a novel approach to diamond creation.
“For over a decade I have been thinking about new ways to grow diamonds, as I thought it might be possible to achieve this in what might be unexpected (per ‘conventional’ thinking) ways,” Ruoff explained in an email to Live Science.
The Innovative Experimental Setup
The new method involves a specially designed 2.4-gallon (9-liter) chamber, created by co-author Won Kyung Seong. This chamber can be prepared for experiments in just 15 minutes, allowing for rapid testing of various metal and gas combinations. After extensive trials, the team discovered that a mixture of gallium, nickel, iron, and a small amount of silicon was ideal for catalyzing diamond growth.
The New Synthesis Process
In this process, the four liquid metals—gallium, iron, nickel, and silicon—are blended at a temperature of 1,877 degrees Fahrenheit (1,025 degrees Celsius) under normal atmospheric pressure. This mixture is placed in a graphite case within a custom vacuum chamber that quickly heats and cools the metal while it is exposed to methane and hydrogen gases.
The exposure to these gases causes carbon atoms from methane to diffuse into the melted metal, forming diamond seeds. Within just 15 minutes, diamonds begin to appear at the base of the crucible. In two and a half hours, a more complete diamond film develops, demonstrating the efficiency of this new technique.
Catalytic Activation and Carbon Diffusion
“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,” the researchers explained in their paper. This catalytic process is key to the rapid and efficient diamond formation, setting it apart from the HPHT method.
Potential Implications and Future Prospects
This new method of diamond synthesis at normal atmospheric pressure and moderate temperatures could revolutionize various industries. It offers a more environmentally friendly and cost-effective alternative to traditional diamond production. The rapid synthesis time means that diamonds can be produced more quickly and efficiently, potentially reducing costs and increasing the availability of synthetic diamonds.
The technique has significant implications for industries relying on diamond materials, including electronics, cutting tools, and jewelry. As the technology develops, it could lead to further advancements and wider applications.