Research Seminar of Prof. Yusuke Yamauchi and Prof. Jung Ho Kim from University of Wollongong

Lecture Time: 10:00 on 20th January, 2017

Lecture Room: C501 of Science and Innovation Building

Lecture Title: Inorganic Chemistry for Tailored Design of Crystalline Nanoporous Materials

Yusuke Yamauchi

University of Wollongong, Squires Way, North Wollongong, NSW 2500, Australia2Department of Chemistry, National University of Singapore, 117543, Singapore

Abstract

The research on mesoporous (nanoporous) materials, conducted mainly by using surfactant assemblies as templates, has been increasing rapidly. The specific features of regular pore arrangement, uniform mesopore size, and high surface area make these materials very promising for various applications. In this presentation, we will summarize our recent progress on this field.

(1) A mesostructured tin phosphate (SnPi) material has been prepared in the presence of an amphiphilic block copolymer (F127), tin chloride (SnCl4), and phosphoric acid (H3PO4) in an ethanol-water mixed solvent medium. The mesoporous SnPi material, with a large pore diameter (7.4 nm), nanocrystalline walls, a high surface area (310 m2 g−1), and a unique flake-like particle shape, is successfully synthesized by a two-step heat treatment of the parent mesostructured SnPi under flowing N2 gas followed by flowing air. Under moderate conditions (293 K and 60% relative humidity), our mesoporous SnPi shows 6.5 times more proton (H+) conductivity compared to its non-porous/bulk analogue (SnPi-B), due to its higher surface area and unique nanocrystalline porous structure enriched with free O-H groups.

(2) We demonstrate a simple and versatile method to grow monodisperse CH3NH3PbBrxIx-3 perovskite nanocrystals inside mesoporous silica templates. The size of the nanocrystal is governed by the pore size of the templates (3.3, 3.7, 4.2, 6.2, and 7.1 nm). Quantum confinement was obse rved by tuning the size of the particles via the template. This approach provides an additional route to tune the optical bandgap of the nanocrystal. Photoluminescence measurements on CH3NH3PbBr clearly show a shift from green to blue as the pore size is decreased.

Biography:

Prof. Yusuke Yamauchi received his bachelor's degree (2003), master's degree (2004), and Ph.D. (2007) from the Waseda University, Japan. After receiving his Ph.D., he joined NIMS to start his own research group. From 2016, he joined the University of Wollongong as a full professor. He is concurrently serve a visiting professor at several universities (Tianjin University, King Saud University, and Waseda University) and as a honorary group leader of NIMS. He has published 450 papers in international refereed journals with 20,000 citations (h-index 65). He was selected as a Highly Cited Researchers in Chemistry (Thomson Reuters) in 2016.