Layer-by-layer assembled porous photoanodes for efficient electron collection in dye-sensitized solar cells

Layer-by-layer (LbL) assembly is a versatile approach to generate hybrid materials with unique properties. Here, LbL is employed to insert genetically engineered M13 bacteriophage nanowires into a porous polymeric network for efficient dye-sensitized solar cell (DSSC) photoanodes. Both dip and spray LbL processes can be utilized in fabricating novel porous titanium dioxide (TiO2) photoanodes that exhibit advantageous electron transport properties, characterized by a longer electron diffusion length compared to the nanoparticle DSSC. Incorporation of the high aspect-ratio M13 bacteriophage, which yields electron percolation pathway and facilitates electron diffusion within the photoanode, is shown to further enhance the efficiency and the diffusion length in DSSCs.