Transformation from a high-temperature superconductor yttrium-barium-copper oxide to a photocatalytic material yttrium-barium oxide, a DFT-based investigation

• Published in: Computational materials science 2022-10, Vol.213, p.111558, Article 111558
• Main Authors: Cao, Run-Ze, Zhang, Li-Juan, Ding, Ling-Yun, Liu, Xi-Ping, Liu, Xiao-Yan, Jin, Peng, Liu, Si-Tong, Tao, Hu-Chun
• Format: Article
• Language: English
• Subjects: Density functional theory; Electronic structure; Photocatalyst; YB3O/YB4O; Yttrium-barium oxide
• ISSN: 0927-0256; 1879-0801
• DOI: 10.1016/j.commatsci.2022.111558

[Display omitted] •Two novel yttrium-barium oxide photocatalysts, YBO, were discovered based on YBCO.•The energy band, density of states and charge density difference of YB3O and YB4O were analyzed and compared.•Electron spin polarization enables efficient separation of photogenerated carriers generated by YBO.•YB3O and YB4O had good semiconductor properties and photocatalytic potentials. Novel semiconductor photocatalysts are currently a hot research topic. We are inspired by the phenomenon that high-temperature superconductors can achieve superconductivity only under certain conditions (e.g., liquid nitrogen temperature). Here, based on the analysis of the energy band structure of the high-temperature superconductor YBCO (YBa2Cu3O7-x, YBCO), two new yttrium barium oxide (YBO) semiconductor materials, Y2Ba3O6 (YB3O) and Y2Ba4O7 (YB4O), are reported in this study. According to first-principles calculations, we find that YB4O and YB3O have stable formation energies, as well as forbidden band gaps, which are suitable for the visible light response. In addition, YB4O possesses a larger effective mass difference of carrier and stronger electron delocalization in various directions than that of YB3O, while YB3O possesses a larger light absorption threshold than that of YB4O. These two innovative yttrium-barium oxide materials show strong semiconducting properties and have great potential as photocatalysts.