The inevitable amorphous Bi₂O₃ on the surface of plasmonic Bi nanospheres serving as the recombination center of hot electron-hole pairs, hindered the transfer of photo-generated hot electrons and production of reactive oxygen species (ROS) seriously. In this study, Bi@amorphous Bi₂O₃ was transformed to Bi@crystal Bi₂O₂CO₃ by secondary hydrothermal reaction. Bi@Bi₂O₂CO₃ core-shell photocatalyst exhibited higher visible-light catalytic activity (34.1%) than Bi@Bi₂O₃ did (12.3%) in terms of NO_x removal. Photoelectrochemical, surface photovoltage spectroscopy spectra and Kelvin probe force microscopy measurement results indicate that Bi₂O₂CO₃ shell reduced the transmission resistance of hot electrons excited from Bi core. O₂-TPD, trapping experiments and density functional theory further confirmed that the transferred hot electrons were a help for ROS generation and •O₂⁻ radicals were the major contributor. This study not only addresses the unsettled issue of surface amorphous Bi₂O₃, but also provides a facile method to transform the amorphous shell to crystal phase of core-shell photocatalyst and new insights into the hot electrons separation and the formation of main ROS over the surface crystal transition of plasmonic Bi.

作为热电子-空穴对的复合中心的等离激元Bi纳米球表面不可避免的非晶态Bi ₂ O ₃严重阻碍了光生热电子的转移和活性氧（ROS）的产生。在这项研究中，铋@无定形的Bi ₂ ö ₃转化到毕@晶体的Bi ₂ ö ₂ CO ₃通过二次水热反应。就NO _x而言，Bi @ Bi ₂ O ₂ CO ₃核壳光催化剂显示出比Bi @ Bi ₂ O ₃更高的可见光催化活性（34.1％）（12.3％）移动。光电化学，表面光电压光谱和开尔文探针力显微镜测量结果表明，Bi ₂ O ₂ CO ₃壳层降低了Bi核激发的热电子的传输电阻。Ø ₂ -TPD，诱捕实验和密度泛函理论进一步证实了转热电子是活性氧产生和•ø帮助₂ ^-自由基是主要的贡献者。这项研究不仅解决了表面非晶态Bi ₂ O ₃的未解决问题。，但也提供了一种将非晶态壳转化为核壳型光催化剂晶相的简便方法，并提供了新的见解，以了解热电子的分离以及等离激子Bi的表面晶体跃迁上主要ROS的形成。