Fig. 4

Spectroscopic evidence for effective electron transfer process. a Normalized UV–vis of Eu-Ru(phen)3-MOF and H3L in DMF. Inset: Emission spectra of Eu-Ru(phen)3-MOF and H3L (λex = 465 nm). b Normalized luminescence decay traces of Eu-Ru(phen)3-MOF and H3L over the first 50 ns (λex = 377 nm). Inset: Decay transients measured at 630 nm (λex = 465 nm). c Transient absorption spectra of Eu-Ru(phen)3-MOF and H3L at various time delays, and d corresponding kinetic traces at 604 nm