Undoped Layered Perovskite Oxynitride Li2 LaTa2 O6 N for Photocatalytic CO2 Reduction with Visible Light

Takayoshi Oshima; Tom Ichibha; Ken Sinkou Qin; Kanemichi Muraoka; Junie Jhon M Vequizo; Keisuke Hibino; Ryo Kuriki; Shunsuke Yamashita; Kenta Hongo; Tomoki Uchiyama; Kotaro Fujii; Daling Lu; Ryo Maezono; Akira Yamakata; Hideki Kato; Koji Kimoto; Masatomo Yashima; Yoshiharu Uchimoto; Masato Kakihana; Osamu Ishitani; Hiroshi Kageyama; Kazuhiko Maeda

doi:10.1002/anie.201803931

Undoped Layered Perovskite Oxynitride Li₂ LaTa₂ O₆ N for Photocatalytic CO₂ Reduction with Visible Light

Angew Chem Int Ed Engl. 2018 Jul 2;57(27):8154-8158. doi: 10.1002/anie.201803931. Epub 2018 May 30.

Authors

Takayoshi Oshima^{1

2}, Tom Ichibha³, Ken Sinkou Qin³, Kanemichi Muraoka^{1

2}, Junie Jhon M Vequizo⁴, Keisuke Hibino¹, Ryo Kuriki^{1

2}, Shunsuke Yamashita⁵, Kenta Hongo^{6

7

8

9}, Tomoki Uchiyama¹⁰, Kotaro Fujii¹, Daling Lu¹¹, Ryo Maezono^{3

9}, Akira Yamakata⁴, Hideki Kato¹², Koji Kimoto⁵, Masatomo Yashima¹, Yoshiharu Uchimoto¹⁰, Masato Kakihana¹², Osamu Ishitani¹, Hiroshi Kageyama¹³, Kazuhiko Maeda¹

Affiliations

¹ Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1-NE-2 Ookayama, Meguro-ku, Tokyo, 152-8550, Japan.
² Japan Society for the Promotion of Science, Kojimachi Business Center Building, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo, 102-0083, Japan.
³ School of Information Science, JAIST, Asahidai 1-1, Nomi, Ishikawa, 923-1292, Japan.
⁴ Graduate School of Engineering, Toyota Technological Institute, 2-12-1 Hisakata, Tempaku, Nagoya, 468-8511, Japan.
⁵ Research Center for Advanced Measurement and Characterization, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki, 305-0044, Japan.
⁶ Research Center for Advanced Computing Infrastructure, JAIST, Asahidai 1-1, Nomi, Ishikawa, 923-1292, Japan.
⁷ Center for Materials Research by Information Integration, Research and Services Division of Materials Data and Integrated System, National Institute for Materials Science, Tsukuba, 305-0047, Japan.
⁸ PRESTO (Japan) Science and Technology Agency, 4-1-8 Honcho, Kawaguchi-shi, Saitama, 322-0012, Japan.
⁹ Computational Engineering Applications Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
¹⁰ Graduate school of Human and Environmental Studies, Kyoto University, Yoshida-nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan.
¹¹ Suzukakedai Materials Analysis Division, Technical Department, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
¹² Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.
¹³ Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan.

Abstract

Oxynitrides are promising visible-light-responsive photocatalysts, but their structures are almost confined with three-dimensional (3D) structures such as perovskites. A phase-pure Li₂ LaTa₂ O₆ N with a layered perovskite structure was successfully prepared by thermal ammonolysis of a lithium-rich oxide precursor. Li₂ LaTa₂ O₆ N exhibited high crystallinity and visible-light absorption up to 500 nm. As opposed to well-known 3D oxynitride perovskites, Li₂ LaTa₂ O₆ N supported by a binuclear Ru^II complex was capable of stably and selectively converting CO₂ into formate under visible light (λ>400 nm). Transient absorption spectroscopy indicated that, as compared to 3D oxynitrides, Li₂ LaTa₂ O₆ N possesses a lower density of mid-gap states that work as recombination centers of photogenerated electron/hole pairs, but a higher density of reactive electrons, which is responsible for the higher photocatalytic performance of this layered oxynitride.

Keywords: CO2 reduction; oxynitride; perovskites; photocatalysis; visible light.

Publication types

Research Support, Non-U.S. Gov't