Picosecond absorption studies of photoinduced charge separation in polyelectrolyte bound aromatic chromophores

✍ Scribed by M.A. Shand; M.A.J. Rodgers; S.E. Webber

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 451 KB
• Volume: 177
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(91)90167-8

✦ Synopsis

Picosecond absorption studies of photoinduced electron transfer between aromatic chromophores bound to polymethacrylic acid (P) and methylviologen (MVz+) have been carried out in aqueous solution. The diphenylanthracene copolymer/viologen system at pH 2.8 shows the corresponding redox products DPA+' and MV+' arising from the singlet state of DPA with a fonvard rate constant of electron transfer of 2.6 x 1 O9 SC'. At pH 9.0 the quenching of the S, state of DPA occurs with no charge separated products being observed. The pyrene copolymer shows no evidence of charge separated products at any pH in the range 2.8-9.0. It is proposed that the differences in the radical pair kinetics arise from differences in the degree of binding of the ground state complexes formed by the donor and acceptor species.