Novel Functional Energy Materials with Mixed Anions

Date: 2021/12/06 - 2021/12/06

Academic Seminar: Novel Functional Energy Materials with Mixed Anions

Speaker: Dr. Cedric Tassel, Associate Professor in Kyoto University, Japan

Time: 1:30 p.m.-2:30 p.m., Dec 6th, 2021 (Beijing Time)

Location: via Feishu

Abstract

Most minerals found in nature and manmade ceramic materials are oxides, halides, or chalcogenides. These single anion compounds have been explored for over a century and are extensively used in numerous energy-related devices from semi-conductors, ferroelectrics, catalysts to battery materials.

The use of multiple anions with different sizes, polarizability, and electronegativity in a solid framework (oxyhydrides, oxynitrides, chalcohydrides) provide new degrees of freedom to engineer the properties of materials. Tuning the anionic content of a structure allows to yield better migration paths for ions in solid state electrolytes, control the symmetry of ferroelectrics, engineer the electronic structures for photovoltaics, and enhance catalytic properties for ammonia production and CO2 reduction. Although these mixed-anion structures are extremely attractive from functional and energy device perspectives, they are challenging to prepare owing to the different volatilities and decompositions of precursors (hydrides, halides) at the high temperatures required for conventional ceramic synthesis.

In this seminar, we will discuss the key strategies we have developed to generate novel functional energy materials with multiple anions and present our recent results on novel fast alkali-ion conducting antiperovskites and room temperature hydride H– conductors.

Biography

Cédric Tassel is currently an associate professor in Kyoto University, Japan. He received his Bachelor’s and Master’s degree from the University of Rennes I in France and next moved to Japan where he obtained his PhD in 2010 from Kyoto University. His current interests are focused on the exotic syntheses and characterization of perovskite-related and two-dimensional structures for functional energy materials.