to understand the charge-transfer processes of the self-assembled system and lifetime of transient photosensitiser states. Visible excitation of Rubpy complexes results in a metal-to-ligand charge transfer (MLCT) to give the charge-separated excited state [Ru III (bpy •-)(bpy)2] 2+ (Ru*). Tracking the Ru* PL at 620 nm shows that C12E6 increases the RubpyC17* lifetime, but does not affect the hydrophilic Rubpy* (Fig 2A, S5-6 and Table ). This longer RubpyC17* lifetime is attributed to C12E6 decreasing the local RubpyC17 concentration in micelles and thereby limiting self-quenching and allowing more time for reductive quenching by ascorbate, which reduces the Ru III centre of Ru* to form [Ru II (bpy •-)(bpy)2] + (denoted Ru -). Tracking Ru -formation with TAS (510 nm probe) shows that adding C12E6 increases the RubpyC17 -yield by 50%, resulting in a quenched photosensitiser yield that is only 25% lower than diffusionally free Rubpy - ). The RubpyC17 - lifetime is then 18-fold longer than Rubpy -with C12E6 and phosphate buffer (282 vs 16 µs; Fig 2B and Table ), allowing more time for electron transfer to the catalyst. Adding CoPyPC16 results in deeper absorbance bleaching because its Soret band (max 440 nm; Fig S10 ) is convoluted with Rubpy (max 456 nm). However, CoPyPC16 increases the RubpyC17 -lifetime by 33% rather than oxidising it (282 to 375 µs at 510 nm and lack of bpy •-decay at 366 nm; Fig 2C and). The rapid formation of CoPyPC16 -(broad response at 550-750 nm within 10 µs), the longer RubpyC17 -lifetime, and the relevant redox potentials indicates that HAsc -is oxidised by RubpyC17* to form Asc • , which then reduces CoPyPC16 and forms dehydroascorbate. This pathway prevents charge recombination between Asc • and RubpyC17 -by forming CoPyPC16 -. It also means the system extracts two electrons from the donor per photon, with the process enabled by the high local concentrations inside the micelles. Further TAS analysis including for the ionic surfactants is provided in supplementary information (SI Note 1).