Covalent functionalisation with alkyl tails is a common method for supporting molecular catalysts and photosensitisers onto lipid bilayers, but the influence of the alkyl chain length on the photocatalytic performances of the resulting liposomes is not well understood. In this work, we first prepared a series of rhenium-based CO 2 -reduction catalysts [Re(4, 9, 12, 15, 17, and 19). We then prepared a series of PEGylated DPPC liposomes containing RuC n and ReC n , hereafter noted C n , to perform photocatalytic CO 2 reduction in the presence of sodium ascorbate. The photocatalytic performance of the C n liposomes was found to depend on the alkyl tail length, as the turnover number for CO (TON) was inversely correlated to the alkyl chain length, with a more than fivefold higher CO production (TON = 14.5) for the C 9 liposomes, compared to C 19 (TON = 2.8). Based on immobilisation efficiency quantification, diffusion kinetics, and time-resolved spectroscopy, we identified the main reason for this trend: two types of membranebound RuC n species can be found in the membrane, either deeply buried in the bilayer and diffusing slowly, or less buried with much faster diffusion kinetics. Our data suggest that the higher photocatalytic performance of the C 9 system is due to the higher fraction of the more mobile and less buried molecular species, which leads to enhanced electron transfer kinetics between RuC 9 and ReC 9 .

Nonreactive surfactant molecules have long been used and characterized for a wide range of applications in industries, life science, and everyday life. Recently, new types of functional amphiphilic molecules have emerged that bear another function, for example, a light-absorbing action, or catalytic properties. However, the surfactant properties of these molecules remain to date essentially unknown. In this context, we investigated here the interfacial activity of photocatalytic surfactants based on a ruthenium(II) tris-bipyridine core, functionalized with two alkyl tails. We realized a systematic characterization of the surfactant properties of these molecules at a water–air interface and studied the effect of the alkyl chain length and of the counterions (hexafluorophosphate or chloride) on these properties. Our data demonstrate that ruthenium surfactants with chloride counteranions form a denser layer at the interface, but their surfactant properties can dramatically deteriorate when the chain length of the alkyl tail increases, leading to simple hydrophobic molecules with poor surfactant properties for the longest chains (C17). These findings pave the way for a better use and understanding of photocatalytic soft interfaces.

Electrocatalysis is to play a key role in the transition towards a sustainable chemical and energy industry and active, stable and selective redox catalysts are much needed. Porous structures such as metal organic frameworks (MOFs) are interesting materials as these may influence selectivity of chemical reactions through confinement effects. In this work, the oxygen reduction catalyst Cu‐tmpa was incorporated into the NU1000 MOF. Confinement of the catalyst within NU1000 steers the selectivity of the oxygen reduction reaction (ORR) towards water rather than peroxide. This is attributed to retention of the obligatory H2O2 intermediate in close proximity to the catalytic center. Moreover, the resulting NU1000|Cu‐tmpa MOF shows an excellent activity and stability in prolonged electrochemical studies, illustrating the potential of this approach.