Molecular-based dye-sensitized photoelectrochemical cells (DSPECs) have traditionally targeted solar-driven water splitting for the conversion of solar energy into fuels in aqueous media. This work reports the use of a DSPEC-type photoanode specifically designed to carry out chemoselective oxidation of benzylic alcohol moieties in lignin model compounds and real lignin in organic media. The TiO 2 -based photoanode incorporates a surface-bound Ru(II)-based photocatalyst and solutiondissolved hydrogen atom transfer (HAT) co-catalyst to perform solar-driven photocatalytic oxidation of the lignin substrates. Under aerobic conditions with simulated solar illumination, conversion efficiencies in excess of 90% are observed for the formation of the oxidized ketone product from model compounds. The DSPEC half-cell exhibited impressive long-term durability, sustaining photocatalytic oxidation of the lignin model compound over a net illumination period of 80 h. This photoelectrochemical heterogeneous catalytic process provides a unique foundation to perform selective C−O bond cleavage for real lignin conversion technologies.

Pyclen and cylen complexes of manganese show pH dependent catalase activity with improved TOF and TON for the more rigid pyclen derivative. Spectroscopic investigation shows O2 evolution corresponds with the presence of a μ-O bridged species.