Exploring the Growth Dynamics of Size-selected Carbon Atomic Wires with in situ UV Resonance Raman Spectroscopy

Abstract: Short carbon atomic wires, the prototypes of the lacking carbon allotrope carbyne, represent the fundamental one-dimensional system and the first stage in carbon nanostructure growth, which still exhibits many open points regarding their growth and stability. We introduce an in situ UV resonance Raman approach for real-time monitoring of the growth of carbon atomic wires during pulsed laser ablation in liquid without perturbing the synthesis environment. We track single-chain species' growth dynamics, achieving size selectivity by exploiting the peculiar optoelectronic properties of carbon wires and the tunability of synchrotron radiation. We systematically explore diverse solvents, finding size- and solvent-dependent production rates linked to the solvent's C/H ratio and carbonization tendency. Carbon atomic wires' growth dynamics reveal a complex interplay between formation and degradation, leading to an equilibrium. Water, lacking in carbon atoms and reduced polyynes' solubility, yields fewer wires with rapid saturation. Organic solvents exhibit enhanced productivity and near-linear growth, attributed to additional carbon from solvent dissociation and low relative polarity. Exploring the dynamics of the saturation regime provides new insights into advancing carbon atomic wires' synthesis via PLAL. Understanding carbon atomic wires' growth dynamics can contribute to optimizing PLAL processes for nanomaterial synthesis.