Research Progress of Plasma Discharge in the Chemical Evolution of Life

Origin and evolution of life are among humanity's ultimate enigmas.Classical chemical-origin hypotheses confront several key challenges, including the activation of chemically inert molecular gases, the transformation of simple molecules into complex functional ones, the emergence of biomolecular homochirality, and the origin of the genetic code.Since the pioneering Miller-Urey discharge experiment, plasma discharges have been regarded as one plausible setting for the emergence of life's molecules.As a high-energy, non-equilibrium environment, plasma can drive molecular fragmentation and recombination through reactive species such as energetic electrons, ions, and radicals, thereby providing crucial physicochemical underpinnings for the formation of complex organic molecules and the progressive increase of molecular complexity.Recent decades have witnessed significant advances in this field.Laboratory simulations have shown that plasma discharges in N2-CH4 or CO-H2 atmospheres can efficiently generate hydrogen cyanide, formaldehyde, and other small molecules that serve as precursors of amino acids, nucleobases, and sugars.Beyond monomer synthesis, plasma environments have been found to promote polymerization reactions leading to oligopeptides and nucleic acid fragments, demonstrating a feasible route from simple molecules to biopolymers.Moreover, plasma-driven chemistry at interfaces such as microdroplets, aerosols, and underwater bubbles provides unique microenvironments that concentrate reactants and stabilize products, thereby facilitating molecular assembly and enhancing the plausibility of prebiotic reactions.Plasma studies have also offered insights into fundamental questions such as the origin of homochirality.Experimental evidence indicates that asymmetric reaction pathways may be favored under plasma irradiation when combined with mineral surfaces or circularly polarized light, suggesting possible mechanisms for chiral selection.Furthermore, coupling plasma discharge with catalytic platforms or microfluidic devices has recently emerged as a promising direction, allowing controlled studies across scales that mimic primitive Earth environments.This review summarizes the state of the art in plasma-based prebiotic chemistry, highlights key challenges including reproducibility, selectivity, and integration with geological settings, and outlines future perspectives.We propose that interdisciplinary approaches-combining plasma physics, geochemistry, catalysis, and space chemistry-will be essential to unravel how plasma contributed to the chemical origins of life.Such studies not only enrich our understanding of life's beginnings on Earth but may also provide new frameworks for assessing the potential for life in extraterrestrial environments such as Titan or exoplanetary atmospheres.