Investigation of n-type co-doping in barium stannate nanoparticles

Abstract

Barium stannate (BaSnO3) has recently emerged as an ideal candidate for use as a transparent electrode, especially when appropriately doped. Whilst research has been conducted on the effects of using various elements to dope BaSnO3, to date there has been no systematic study into the role of two separate elements doping both sites at once. Here, were present an in-depth investigation into the optical and crystallographic effects of simultaneously doping the barium stannate crystal at both cationic sites. A wet chemical methodology to synthesize BaSnO3 nanoparticles that enables tunable doping with lanthanum (at the Ba site) and/or antimony (at the Sn site) is developed. Doping is validated via energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and absorption spectroscopy in the visible and near infrared range. Through high-resolution X-ray diffraction (XRD) and transmission electron microscopy (TEM) we assessed the effect of doping on the crystal size and strain, and then evaluated the role of each dopant in affecting the plasmonic properties of the BaSnO3 nanoparticles as a function of dopant concentration and annealing temperature. We show that doping across both sites results in less lattice strain, less defects, and overall larger particles, and through a systematic study we provide design rules to synthesize high-quality BaSnO3-based nanomaterials.