RESUMEN

This paper reports the synthesis of Au nanoparticles by 30-fs pulses irradiation of a sample containing HAuCl4 and chitosan, a biopolymer used as reducing agent and stabilizer. We observed that it is a multi-photon induced process, with a threshold irradiance of 3.8 × 10(11) W/cm2 at 790 nm. By transmission electron microscopy we observed nanoparticles from 8 to 50 nm with distinct shapes. Infrared spectroscopy indicated that the reduction of gold and consequent production of nanoparticles is related to the fs-pulse induced oxidation of hydroxyl to carbonyl groups in chitosan.

Asunto(s)

Quitosano/química , Quitosano/efectos de la radiación , Oro/química , Oro/efectos de la radiación , Rayos Láser , Nanopartículas/química , Nanopartículas/efectos de la radiación , Ensayo de Materiales