Biotemplated Synthesis of TiO2‑Coated Gold Nanowire for Perovskite Solar Cells
journal contributionposted on 06.09.2017, 14:19 by Ippei Inoue, Yuki Umemura, Itaru Raifuku, Kenichi Toyoda, Yasuaki Ishikawa, Seigo Ito, Hisashi Yasueda, Yukiharu Uraoka, Ichiro Yamashita
Fibrous nanomaterials have been widely employed toward the improvement of photovoltaic devices. Their light-trapping capabilities, owing to their unique structure, provide a direct pathway for carrier transport. This paper reports the improvement of perovskite solar cell (PSC) performance by a well-dispersed TiO2-coated gold nanowire (GNW) in a TiO2 cell layer. We used an artificially designed cage-shaped protein to synthesize a TiO2-coated GNW in aqueous solution under atmospheric pressure. The artificially cage-shaped protein with gold-binding peptides and titanium-compound-biomineralizing peptides can bind GNWs and selectively deposit a thin TiO2 layer on the gold surface. The TiO2-coated GNW incorporated in the photoelectrodes of PSCs increased the external quantum efficiency within the range of 350–750 nm and decreased the internal resistance by 12%. The efficient collection of photogenerated electrons by the nanowires boosted the power conversion efficiency by 33% compared to a typical mesoporous-TiO2-nanoparticle-only electrode.