One-Pot Synthesis of Anatase, Rutile-Decorated Hydrogen Titanate Nanorods by Yttrium Doping for Solar H2 Production

Sovann Khan; Hiroshi Ikari; Norihiro Suzuki; Kazuya Nakata; Chiaki Terashima; Akira Fujishima; Ken-Ichi Katsumata; Vicente Rodríguez-González

doi:10.1021/acsomega.0c02855

One-Pot Synthesis of Anatase, Rutile-Decorated Hydrogen Titanate Nanorods by Yttrium Doping for Solar H₂ Production

ACS Omega. 2020 Aug 31;5(36):23081-23089. doi: 10.1021/acsomega.0c02855. eCollection 2020 Sep 15.

Authors

Sovann Khan¹, Hiroshi Ikari¹, Norihiro Suzuki^{1

2}, Kazuya Nakata^{1

3}, Chiaki Terashima^{1

2}, Akira Fujishima¹, Ken-Ichi Katsumata^{1

2

4}, Vicente Rodríguez-González^{1

5}

Affiliations

¹ Photocatalysis International Research Center, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510, Japan.
² Research Center for Space Colony, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510, Japan.
³ Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-0012, Japan.
⁴ Department of Materials Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan.
⁵ División de Materiales Avanzados, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), Camino a la Presa San José 2055, Lomas 4a Sección, San Luis Potosí 78216, Mexico.

Abstract

We have prepared yttrium (Y)-doped hydrogen titanate nanorods (HTN) by a microwave-assisted hydrothermal method. Y-doped HTN showed much improved photocatalytic activities for both H₂ evolution and dye decomposition. H₂ production from a methanol-water solution under UV-visible light for 7 h was enhanced by a factor of 5.5 with 1 wt % Y-doping. Doping with Y³⁺ ions reduced the band gap of HTN by ∼0.28 eV and induced new phases of anatase and rutile. High photocatalysis by Y-doping was attributed to enhanced light absorption (smaller band gap) and effective charge separation (heterojunction). To optimize H₂ production, a series of experiments examining effects of doping concentrations and non-noble surface metal (e.g., Ni, Cu, Co) loading were carefully performed. Y-doping in this work is a new and promising approach for synthesizing highly active HTN by producing the HTN/rutile/anatase heterostructure within the one-pot method.