Binding of a graphene-protein antenna complex-A computational study

Resumen

In the search for novel and more efficient photovoltaic devices, dye-sensitized solar cells (DSSCs) are particularly promising, thanks to their high performance and sustainable manufacture. Recently, a DSSC device based on the immobilization of a modified light-harvesting protein of Chlamydomonas reinhardtii (LHCA4) on a graphene oxide electrode through covalent bonding, was designed as a strategy to control the orientation of the protein. In this work, an atomistic model for the corresponding antenna complex has been generated, and the effects of the covalent binding on its structural and morphological properties have been explored through molecular dynamics (MD) simulations. The analysis of different trajectories, corresponding to complexes with varying numbers of protein-graphene covalent bonds, size of the graphene oxide layers, and initial relative orientation, suggest that the immobilization process may induce some changes in the protein conformation, but still maintaining a substantial portion of its tertiary structure. In addition, a preference to a particular orientation of the LHCA4 molecule, of about 60 degrees with respect to the graphene layer, is observed, giving support to the potential of the experimental approach to control the relative arrangement of the complex components in this type of device. The synergy between computational and experimental approaches opens the way to exciting opportunities in materials development, fostering innovation and improving optoelectronic device efficiency.