Dave Mao’s research centers on ultra-high pressure physics, chemistry, material sciences, geophysics, geochemistry and planetary sciences using diamond-anvil cell techniques that he has pioneered. He is also director of the Energy Frontier Research in Extreme Environments (EFree) center at the Geophysical Laboratory and he is director of the High Pressure Synergitic Center (HPSynC) and the High Pressure Collaborative Access Team (HPCAT) at the Advanced Photon Source, Argonne National Laboratory, IL.
Mao pioneered the diamond anvil cell, an instrument designed to subject materials to high pressures and temperatures by squeezing matter between two diamond tips. Over the years Mao has improved on both the diamond anvil cell and measurement instrumentation that reveals the properties of materials as they undergo extreme conditions. He has made many important discoveries about the chemical, structural, and other physical characteristics of matter along the way.
In one study, Mao and colleagues subjected a mixture of hydrogen and water to a pressure of about 220 megapascals (2,000 times atmospheric pressure) at room temperature (300 K or 80°F), which formed a clathrate hydrate—a cage-like framework of water molecules enclosing molecules of gas. Unlike most clathrate hydrates, where only one molecule of a gas can be trapped in each of the H2O cages, multiple hydrogen molecules were entrapped in this material. This finding may be important to the development of hydrogen storage devices—a prerequisite to using hydrogen as fuel.
In another study Mao and colleagues transformed graphite, the soft “lead” of pencils, into a material that competes in strength with its molecular cousin diamond. Mao also explores what happens to elements in planetary cores. He is looking at defining thermodynamic, elastic, and vibrational parameters of elements such as iron and hydrogen at core conditions. This work is important to basic research and for understanding seismological phenomena.
Mao received a B.Sc. in geology from National University in Taiwan, China in 1963. He received a MS.c. and Ph.D. from the University of Rochester in 1966 and 1968. Between 19968 and 1972 he was a postdoctoral fellow and research associate at Carnegie. He was appointed staff scientist in 1972. For more see the Mao lab