Amyloid Directed Synthesis of Titanium Dioxide Nanowires and Their Applications in Hybrid Photovoltaic Devices

This paper reports beta-lactoglobulin amyloid protein fibrils directed synthesis of Titanium Dioxide (TiO2) hybrid nanowires. Protein fibrils act as templates to generate closely packed TiO2 nanoparticles on the surface of the fibrils using titanium (IV) bis (ammonium lactato) dihydroxide (TiBALDH) as precursor, resulting in the TiO2coated amyloid hybrid nanowires. These amyloid fibrils also exhibit complexation with a luminescent water-soluble semiconductive polythiophene (P3HT). TiO2 nanowires behave as electron acceptor while, P3HT as electron donor. In this way, amyloid-TiO2 hybrid nanowires can serve in heterojunction photovoltaic devices. To demonstrate this, a photovoltaic active layer is prepared by spin coating the blended mixture of polythiophene-coated fibrils and amyloid-TiO2 hybrid nanowires. The currentvoltage characteristics of these photovoltaic devices exhibit excellent fill factor of 0.53, photovoltaic current density of 3.97 mAcm-2 and power conversion efficiency of 0.72%, highlighting a possible future role for amyloid-based templates in donoracceptor devices, organic electronics and hybrid solar cells.