Effect of radiation dose on the size of bismuth particles produced by radiolysis
Résumé
Colloidal bismuth is formed in $\gamma$-irradiated solutions , containing BiO +, 0.2 M propanol-2 and $2\times 10^{-2}$ M of polyacrylic acid. Radiolytic reduction of these solutions produces long-lived bismuth clusters which are stabilized on the polymer chains. The clusters have a distinct absorption band at 350 nm with a tentatively assigned to Bi n0 or Bi nx+ structures. With continued irradiation, the clusters coalesce into colloidal particles of 5 nm diameter. The absorption spectra of Bi oligomers and colloidal particles are reported as well as the optical changes accompanying their formation.