Photocatalysis. Previously, we have shown that NU1K can act as a light-harvesting antenna to transfer redox equivalents to node-anchored redox quenchers and redoxcatalysts. We reasoned that similar behavior might be seen here. We then qualitatively evaluated suspensions of CoMo6S24@NU1K as photocatalysts for hydrogen evolution. To regenerate the light-absorbing tetraphenyl-pyrene linker following electron-transfer to a PTM-based catalyst we employed a sacrificial electron donor, triethanolamine (TEOA). For these preliminary experiments we relied upon residual water in the solvent acetonitrile as a proton source, while recognizing that TEOA might also function as a proton source. We irradiated CoMo6S24@NU1K suspensions with the reaction mixture at 390 nm light, and recorded H2 evolution for 30 h. As shown in Figure , 10 mmol of H2 were obtained per gram of contained CoMo6S24 catalyst. Assuming, for simplicity, one active-site pair per PTM, this amount translates to ~28 catalytic turnovers.