First principles electric structure calculation of double perovskite photocatalyst

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05140
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 34030:Green sustainable chemistry and environmental chemistry-related
• Research Institution: Iwate University
• Principal Investigator: Nishidate Kazume 岩手大学, 理工学部, 教授 (90250638)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 光触媒 / ダブルペロブスカイト / 第一原理計算 / 仕事関数

Outline of Final Research Achievements

Although some semiconductors are known to have a photo-catalytic activity, the most commonly used one is the titanium dioxide. However, the titanium dioxide has a large band gap of 3.2 eV and therefore it's photo-catalytic activity is mainly restricted in the UV light region. In this study, we focused on the Ba2PrBiO6 double perovskite which has the photo-catalytic activity in visible light region, and theoretically investigated it's surface electronic structure. We performed extensive first-principles calculation and found that the position of the surface band gap is changed depending on the polar-surface, and also the surface defect can affect the band gap.

Free Research Field

物質科学

Academic Significance and Societal Importance of the Research Achievements

本研究成果は酸化チタンに代わる光触媒として注目をあつめているダブルペロブスカイトについて，その表面電子構造を理論的にあきらかにしたものである。仕事関数を詳細にしらべ，表面バンドギャップが水の解離反応準位に来ることを明らかにした。さらに表面の欠陥によるバンドギャップの変調が，バンドギャップの実験値を説明できることを見いだした。また水分子を表面においた計算から，有限温度において水の吸着と解離が発生することを明らかにした。