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Low temperature plasmas (LTP) are a unique class of open‐driven systems in which chemical reactions are unpredictable using established concepts. The terminal state of chemical reactions in LTP, termed thesuperlocalequilibrium state, is hypothesized to be defined by a proposed set of state variables. Using a LTP reactor wherein the state variables have been measured, it is shown that CO₂spontaneously splits and the effluent speciation is independent of the influent speciation if the state variables are held constant and the residence time is long. CO₂conversion at long residence times, which is expected to be nominally zero from equilibrium thermodynamics, can be as high as 70% in the LTP. The employed low pressure plasma reactor (P= 10 mbar) had a similar volume, productivity, and energy efficiency compared to an atmospheric pressure dielectric barrier discharge reactor, thanks to reaction rates that were three orders of magnitude faster.

III–V semiconductor nanocrystals are an important class of optoelectronic materials. However, the gas‐phase synthesis of these materials, especially of the stibnides, has been left relatively unexplored. In this study, we demonstrate the synthesis of free‐standing GaSb nanocrystals for the first time, using a novel gas‐phase process. We show that when elemental aerosols are used as precursors for Ga and Sb, the elements mix at the nanometer length scale as the aerosols pass through a nonequilibrium plasma reactor. At sufficiently high plasma power, the mixing produces free‐standing GaSb nanocrystals, with a small amount of excess Ga segregated at the periphery of the particles. The reaction is initiated by vaporization of elemental aerosols in the plasma despite the low‐background temperature. Ion bombardment determines the extent of vaporization of Ga and Sb and thereby controls the ensemble stoichiometry and reaction rates.