Electrostatically Driven Multielectron Transfer for the Photocatalytic Regeneration of Nicotinamide Cofactor

Developing generic strategies that are capable of driving multielectron processes are essential to realize important photocatalytic conversions. Here, we present the idea of introducing favorable catalyst–reactant interaction in achieving efficient photocatalytic regeneration of nicotinamide (NADH) cofactor by gold nanoparticles (AuNPs). The electrostatic attraction emanating from the ligands on the surface of NP increases the channeling and local concentration of NAD+ reactants around AuNP photocatalysts, thereby enhancing the probability of the electron transfer process. Detailed kinetics- and intensity-dependent studies confirm the involvement of multiple electron transfer from the AuNP photocatalyst to the NAD+ reactant. The photocatalytic performances of AuNPs presented here are comparable to or greater than most of the catalytic systems reported based on plasmonic NP, with the added advantage of being structurally less complex. The use of electrostatics mimics the underlying force involved in various enzyme catalysis, which can serve as a generic approach for other important artificial multielectron photocatalytic reactions as well.