Nanoprobes for Deep Carbon

• DOI: 10.2138/rmg.2013.75.13
• Publication Date: 2013-02-14T03:07:55Z
• Authors: W. L. Mao; E. Boulard
• Keywords: 0301 basic medicine; 0303 health sciences; 03 medical and health sciences; 13. Climate action

> “Who looks outside, dreams; who looks inside, awakes.” > > — Carl Jung Surficial observations reveal carbon in a great variety of organic, inorganic, and biological forms that subduct with descending slabs and rise and erupt in volcanoes. Due to the lack of experimental means for studying carbon under extreme deep Earth conditions, we have limited information on the density and bonding nature of carbon-bearing fluids, and virtually no information on the texture and porosity of fluid-rock assemblages. Our knowledge on some of the most fundamental questions surrounding the deep carbon cycle becomes increasingly tenuous as we move into the planet. For example, in what form do carbon-bearing materials exist deep within Earth (Oganov et al. 2013)? How does carbon move within the planet’s deep interior (Dasgupta 2013)? To address these types of questions, we need to improve our understanding of carbon-bearing phases at the extreme pressure-temperature conditions existing in Earth. As the fourth most abundant element in the universe, the backbone of organic matter and major energy carriers, pure carbon forms a variety of allotropes including both crystalline and disordered structures such as diamond, graphite, graphene, buckyballs, nanotubes and glassy carbon with numerous and exciting potential in technological applications. Adding the more than 370 other carbon-bearing mineral species (Hazen et al. 2013), this represents a huge range of structures and bonding and fascinating (as well as complex) physics and chemistry. Currently much is unknown about the behavior of carbon-bearing phases at high pressures and temperatures. Experimental study of materials behavior at extreme conditions requires the ability to reach simultaneous high pressure-temperature conditions, and the development and implementation of a battery of micro/nanoscale probes to characterize samples. In addition, studying carbon brings its own set of complications and considerations. In this chapter we first review some of the techniques for reaching ultrahigh …