γ-Ray Driven Aqueous-Phase Methane Conversions into Complex Molecules up to Glycine

Fundamental understanding of initial evolutions of molecules in the universe is of great interest and importance. CH₄ is one of the abundant simple molecules in the universe. Herein we report γ-ray, high-energy photons commonly existing in cosmic rays and unstable isotope decay, as an external energy to efficiently drives aqueous-phase CH₄ conversions to various products with the presence of oxygen at room temperature. Glycine also forms with an additional introduction of ammonia. Both CH₄ conversions and product distributions are modified by solid granules, and a CH₃COOH selectivity as high as 82 % is obtained when SiO₂ is added. Our results point to γ-ray driven aqueous-phase CH₄ conversions as a likely formation network of initial complex organic compounds in the universe and offer an alternative strategy for efficiently utilizing CH₄ as the carbon source to produce value-added products at mild conditions, a long-standing challenging task in heterogeneous catalysis.