多様な光触媒の性能を左右する「ボトルネック」を診断し、設計指針を確立ー大規模材料探索と速度論解析の融合により、高性能光触媒開発を加速ー

2026-08-31 東京科学大学

東京科学大学、東京理科大学、北陸先端科学技術大学院大学の研究チームは、多様な酸化物光触媒の性能を制限する「ボトルネック」を効率的に診断する速度論的評価法を開発した。Materials Projectから候補を絞り、100組成・200試料をハイスループット評価したうえで、光強度と温度への応答を解析。光生成電荷を表面へ供給する過程と、表面で電荷を反応物へ移動させる過程のどちらが律速しているかを判別できることを示した。さらに、OITDという新指標によって材料ごとの電荷供給能力を定量的に評価し、MnやVを含む材料では電荷供給が良好な一方、ScやYを含む材料では電荷供給がボトルネックになりやすいことを発見した。大規模材料探索と速度論解析を融合し、材料ごとに改善すべき過程を特定できる光触媒設計指針を提示した。

図1. 大規模探索と速度論解析を組み合わせた光触媒材料の評価フロー

＜関連情報＞

ハイスループット速度論解析による酸化物光触媒の電荷供給・電荷移動特性の解明
Element-dependent charge-supply and charge-transfer balance in oxide photocatalysts identified by high-throughput kinetic screening

Yohei Cho;Kyo Yanagiyama;Emi Sawade;Sunao Nakanowatari;Toru Wada;Toshiaki Taniike
Journal of Materials Chemistry A Published:21 July 2026
DOI:https://doi.org/10.1039/d6ta04494h

Photocatalyst design is commonly guided by thermodynamic requirements such as band-edge positions and light absorption, but these criteria alone do not determine catalytic performance because charge generation, transport, recombination, and interfacial charge transfer are governed by material-dependent kinetics. Establishing kinetic design principles therefore requires not only large and diverse material libraries, but also throughput-compatible experiments that extract kinetic information across many compositions. Here, we develop a high-throughput kinetic screening strategy for oxide photocatalysts by combining broad materials exploration with temperature- and light-intensity-dependent photocatalytic evaluation. From 82 202 oxygen-containing candidates in the Materials Project, we narrowed the candidate space using safety, synthesizability, and bandgap criteria, randomly selected 100 compositions, and synthesized them at 400 and 1000 °C. Initial screening identified sparse but promising activity among Ag- and Mn-containing oxides. To convert this activity screening into kinetic information, selected active materials were evaluated under controlled temperature and light intensity, enabling classification of their charge-supply and charge-transfer balance using the onset intensity for temperature dependence. The resulting kinetic map shows that elemental identity systematically modulates this balance: Ag-containing oxides with mid-transition metals such as Mn and V tend to exhibit strong charge-supply characteristics, those containing p-block elements such as Al and Bi occupy an intermediate region, and those containing group 3 elements such as Sc and Y are shifted toward charge-supply-limited behavior. These results demonstrate that high-throughput photocatalytic evaluation can be extended beyond empirical activity screening to provide element-dependent kinetic design guidelines for oxide photocatalysts.