Seed-Mediated Growth of Conductive and Transparent Anatase Nb-TiO₂ Films for CdS-Based Devices

Owing to the small natural abundance of indium, high-purity anatase Nb-TiO2 (NTO) is proposed as an alternative of indium tin oxide but materials fabrication is quite difficult. Herein, a simple and scalable seed-mediated method is designed to produce high-purity anatase NTO. Owing to the smaller nucleation free energy of anatase than rutile when the grain size is smaller than 14 nm, nanoscale anatase seeds nucleate preferentially by precise energy control. The mechanism of the seed-mediated NTO is studied by TEM. The conductivity depends on the purity of anatase and high transparency with the optimal antireflection layers is demonstrated by simulation.