M13 Virus-Enabled Synthesis of Titanium Dioxide Nanowires for Tunable Mesoporous Semiconducting Networks

Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. ABSTRACT Mesoporous semiconducting networks exhibit advantageous photo-electrochemical properties. The M13 virus is a versatile biological scaffold that has been genetically engineered to organize various materials into nanowire (NW)-based mesoporous structures. In this study, high aspect-ratio titanium dioxide NWs are synthesized by utilizing M13 viruses as templates and the NWs are assembled into semiconducting mesoporous networks with tunable structural properties. To understand the effects of different morphologies on the photovoltaic performance, the as-fabricated networks are employed as photoanodes in liquid-state dye-sensitized solar cells (DSCs). Compared with traditional nanoparticle-based photoanodes, the NW-based DSC photoanodes demonstrate much higher electron diffusion lengths while maintaining a comparable light-harvesting capacity, thus leading to improved power conversion efficiencies. In addition, the NW-based semiconducting mesoporous thin films are able to load sufficient organolead iodide perovskite materials into the interconnected pores, and the perovskite-coated films are utilized as efficient photoanodes for solid-state organolead iodide perovskite hybrid solar cells (PSCs) and achieve better power conversion efficiencies compared to liquid-state DSCs.