Oxide Analogs of Halide Perovskites and the New Semiconductor Ba2AgIO6

George Volonakis; Nobuya Sakai; Henry J Snaith; Feliciano Giustino

doi:10.1021/acs.jpclett.9b00193

Oxide Analogs of Halide Perovskites and the New Semiconductor Ba₂AgIO₆

J Phys Chem Lett. 2019 Apr 18;10(8):1722-1728. doi: 10.1021/acs.jpclett.9b00193. Epub 2019 Mar 28.

Authors

George Volonakis¹, Nobuya Sakai², Henry J Snaith², Feliciano Giustino¹

Affiliations

¹ Department of Materials , University of Oxford , Parks Road , Oxford OX1 3PH , United Kingdom.
² Department of Physics, Clarendon Laboratory , University of Oxford , Parks Road , Oxford OX1 3PU , United Kingdom.

PMID: 30920840
DOI: 10.1021/acs.jpclett.9b00193

Abstract

The past few years witnessed the rise of halide perovskites as prominent materials for a wide range of optoelectronic applications. However, oxide perovskites have a much longer history and are pivotal in many technological applications. As of today, a rational connection between these important materials is missing. Here, we explore this missing link and develop a novel concept of perovskite analogs, which led us to identify a new semiconductor, Ba₂AgIO₆. It exhibits an electronic band structure remarkably similar to that of our recently discovered halide double perovskite Cs₂AgInCl₆, but with a band gap in the visible range at 1.9 eV. We show that Ba₂AgIO₆ and Cs₂AgInCl₆ are analogs of the well-known transparent conductor BaSnO₃. We synthesize Ba₂AgIO₆ following a low-temperature solution process, and we perform crystallographic and optical characterizations. Ba₂AgIO₆ is a cubic oxide double perovskite with a direct low gap, opening new opportunities in perovskite-based electronics optoelectronics and energy applications.