Elementary reactions of nitrogen and oxygen with boron and carbon at high pressures and temperatures

摘要

The direct elementary reactions among the first and second row elements often yield novel super hard, high energy density, and wide band-gap optical materials. The reactions of oxygen and nitrogen with boron and carbon have been investigated at high pressures and temperatures by using an integrated technique of diamond-anvil cell, laser-heating, x-ray diffraction, Raman spectroscopy. A wide range of products has been synthesized and characterized in-situ at high pressures, including (alpha)-CO(sub 2), B(sub 2)0(sub 3)-I,B(sub 2)0(sub 3)-II, c-BN, h-BN, h(sup ')-B, amorphous carbon nitrides. The elementary reactions occur exothermically and result in highly polycrystallized products with an exception in carbon-nitrogen reactions. The implication of the elementary reactions to energetic materials applications is discussed.