title: BaAu2S2: A Au-Based Intrinsic Photocatalyst for High-Performance Visible-Light Photocatalysis.
abstract: A new Au-based sulfide BaAu2S2was obtained through solid-state reaction. It crystallizes in the tetragonal space group I41/amd with unit cell parameters of a = 6.389 72(2) Å, b = 6.389 72(2) Å, c = 12.7872(1) Å, and Z = 4. Its structure features [AuS2/2]∞zigzag chains composed of corner-sharing AuS2linear units. With a direct band gap of 2.49 eV, BaAu2S2is suitable for the visible-light harvesting. Moreover, it exhibits excellent visible-light photocatalytic activity, which is 1.3 times that of graphitic carbon nitride (g-C3N4) and also demonstrates excellent circulating stability. On the basis of the crystal and electronic structure analysis, the electrons are highly delocalized along the [AuS2/2] chains, and the electron effective mass of BaAu2S2is only approximately one-fifth of that of g-C3N4, which may help the separation of the electron/hole pairs during the photocatalytic process. Additionally, the absorption coefficient of BaAu2S2is extremely high, exceeding 1 × 104cm-1over the entire absorbable visible spectrum (hν > Eg), which is significantly higher than that of g-C3N4. Such factors may contribute to its outstanding photocatalytic performances. According to our best knowledge, BaAu2S2is the first noble metal-based chalcogenide photocatalyst reported as intrinsic light-harvesting and electron/hole-generating centers. This study may provide valuable insights for further research on photocatalytic materials.
authors.affiliation: University of Chinese Academy of Sciences , Beijing 100049, P. R. China.
authors.forename: Molin
authors.initials: M
authors.lastname: Zhou
authors.affiliation: University of Chinese Academy of Sciences , Beijing 100049, P. R. China.
authors.forename: Xin
authors.identifier: http://orcid.org/0000-0002-7836-1784
authors.initials: X
authors.lastname: Jiang
authors.forename: Xingxing
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences , Beijing 100083, P. R. China.
authors.forename: Ke
authors.initials: K
authors.lastname: Xiao
authors.affiliation: University of Chinese Academy of Sciences , Beijing 100049, P. R. China.
authors.forename: Yangwu
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences , Beijing 100083, P. R. China.
authors.forename: Hongwei
authors.identifier: http://orcid.org/0000-0003-0271-1079
authors.initials: H
authors.lastname: Huang
authors.forename: Zheshuai
authors.initials: Z
authors.lastname: Lin
authors.forename: Jiyong
authors.identifier: http://orcid.org/0000-0002-4802-5093
authors.initials: J
authors.lastname: Yao
authors.forename: Chen-Ho
authors.identifier: http://orcid.org/0000-0001-9999-9755
authors.initials: CH
authors.lastname: Tung
authors.forename: Li-Zhu
authors.identifier: http://orcid.org/0000-0002-5561-9922
authors.initials: LZ
authors.lastname: Wu
authors.forename: Yicheng
authors.initials: Y
authors.lastname: Wu