Preparation of polyynes up to C22H2 by liquid-phase laser ablation and their immobilization into SiO2 gel

Long-chain polyynes up to C22H2 were prepared by the liquid-phase laser ablation of a graphite pellet. Short-chain polyynes (C4H2, C6H2, C8H2 and C10H2) prepared simultaneously were identified not by UV–Vis spectra but by LC/MS spectra because C4H2 and C6H2 have absorption peaks at short wavelengths below 200 nm. Polyynes could first be immobilized in a SiO2 dried gel, which was confirmed by UV–Vis spectra of the gel.