  Polyynes are linear carbon chains characterized by alternated single and
triple bonds and terminated by hydrogen or other terminal substituents. They
can be synthesized by pulsed laser ablation in liquid (PLAL) as a scalable,
cost-effective, and fast physical technique. Water can be employed as a solvent
for PLAL to avoid toxicity problems and to reduce costs compared to organic
solvents. However, in this case, the production yield of polyynes reached is
extremely low and prevents further characterization and implementation in new
functional materials. In this work, we synthesized polyynes by pulsed laser
ablation in water and we optimized the process parameters to improve the yield
of polyynes by PLAL. Then, we developed a procedure entirely based on
reversed-phase high-performance liquid chromatography (RP-HPLC) which
effectively enables the concentration, separation and collection of polyynes
according to their length. Since the polyynes sample is an aqueous solution, we
could inject it directly into the RP-HPLC column without the dilution step
required in the case of a sample in an organic solvent. Thanks to our single
RP-HPLC procedure, it is possible to highly increase the concentration and
separately characterize different size-selected polyynes for further use in
functional materials.
