Photoinduced Energy and Electron-Transfer Reactions by Polypyridine Ruthenium(II) Complexes Containing a Derivatized Perylene Diimide

dos Santos, ER; Pina, J; Venancio, T; Serpa, C; Martinho, JMG; Carlos, RM

HERO ID

3575571

Reference Type

Journal Article

Year

2016

HERO ID 3575571
In Press No
Year 2016
Title Photoinduced Energy and Electron-Transfer Reactions by Polypyridine Ruthenium(II) Complexes Containing a Derivatized Perylene Diimide
Authors dos Santos, ER; Pina, J; Venancio, T; Serpa, C; Martinho, JMG; Carlos, RM
Journal Journal of Physical Chemistry C
Volume 120
Issue 40
Page Numbers 22831-22843
Abstract The [Ru(II) (phen)(2)(pPDIp)](2+) complex, where pPDIp is the symmetric bridging ligand phenanthroline-perylene-phenanthroline, shows strong electronic absorption bands attributed to the pPDIp and {Ru(phen)(2)}(2+) moieties in acetonitrile. The charge-separated intermediate {Ru(III) (phen)(2)(pPDIp(-center dot))} was detected by transient absorption spectroscopy upon electronic excitation in either the pPDIp or the complex moieties. The charge-separated intermediate species decays to generate the triplet state (3)*pPDIp-Ru(II) (tau(P) = 1.8 mu s) that sensitizes the formation of singlet molecular oxygen with quantum yield phi(Delta) = 0.57. The dyad in deaerated acetonitrile solutions is reduced by triethylamine (NEt3) to the [Ru(II) (phen)(2)(pPDIp(center dot-))] radical anion in the dark. The electron-transfer reaction is accelerated by light absorption. By photolysis of the radical anion, a second electron transfer reaction occurs to generate the [Ru(II)(phen)(2)(pPDIp(center dot-))] dianion. The changes of the color of solution indicate the redox states of complexes and offer a sensitive reporter of each stage of redox reaction from start to finish. The reduced complexes can be converted to the initial complex, using methyl viologen or molecular oxygen as an electron acceptor. The accumulation of electrons in two well-separated steps opens promising opportunities such as in catalysis.
Doi 10.1021/acs.jpcc.6b06693
Wosid WOS:000385607000009
Is Certified Translation No
Dupe Override No
Is Public Yes