Shape Controlled Plasmonic Sn Doped CdO Colloidal Nanocrystals: A Synthetic Route to Maximize the Figure of Merit of Transparent Conducting Oxide

The synthesis of different anisotropic shaped (eight different shapes) Sn⁴⁺ doped CdO (Sn:CdO) colloidal nanocrystals (NCs) by precise tuning of precursor reactivity and proper choice of capping agent is reported. In all these systems, formation of Sn:CdO quantum dots (QDs) of 2–3 nm is identified at very early stage of reaction. The colloidally stable QDs act as a continuous source for the formation of primary nanoparticles that can be transformed selectively into specific type of nanoparticle morphology. The specific facet stabilization of fcc (face centered cubic)CdO is predicted by particular choice of ligand. Fine tuning of plasmonic absorbance band can be achieved by variation of Sn⁴⁺ doping concentration. Different anisotropic Sn:CdO NCs exhibit interesting shape dependent plasmonic absorbance features in NIR region. High quality crack free uniform dense thin film has been deposited on glass substrate to make high quality transparent conducting oxide (TCO) coatings. figure of merit of TCO can be maximized as high as 0.523 Ω⁻¹ with conductivity of 43 600 S cm⁻¹ and visible transmittance of ≈85% which is much higher than commercially available tin doped indium oxide and other transparent electrodes.