Low-Temperature\nChemical Vapor Deposition of 2D Materials\nvia Single-Atom Catalysis on Liquid Bimetallic Substrates: A Case\nStudy of Graphene Synthesis on Liquid Tin Alloys

Current synthesis and transfer methods of 2D materials\n(2DMs) have\nfallen short of realizing their promised high-end applications on\nan industrial scale. In addressing this gap, the method of chemical\nvapor deposition (CVD) on a liquid substrate envisions cost-effective\ncontinuous synthesis and transfer of single-crystal 2DMs. For practical\nand economical reasons, unlocking effective low-temperature 2DM growth\non a liquid catalyst would be a major milestone. Here, we explore\nthe potential of heterogeneous liquid-phase single-atom catalysts\n(LSACs) for low-temperature 2DM synthesis, specifically the CVD of\ngraphene on liquid Sn–M alloys (M representing a solute metal,\nacting as LSACs). Through systematic screening over the periodic table\nbased on physical properties and quantum chemical calculations, we\nidentified liquid Sn–Ni (92:8 atom %) as a promising candidate.\nExperimental studies in the 1000–1200 K temperature range have\nrevealed clear evidence of catalytic activity by the solute Ni single\natoms in the liquid alloy for graphene synthesis. These results indicate\nthe scientific richness and technological opportunities that LSACs\ncan provide for efficient mass production of 2DMs.