In this work, Bi₂O₃/Bi₂SiO₅ p-n heterojunction photocatalyst was successfully fabricated via a facile one-step synthesis using Bi(NO₃)₃ and nano-SiO₂ as precursors. With the increasing amount of SiO₂, α-Bi₂O₃ gradually transferred into β-Bi₂O_3, and Bi₂O₃/Bi₂SiO₅ p-n heterojunction was obtained at the same time. The as-prepared samples were systematically characterized by XRD, scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectroscopy (DRS). The Bi₂O₃/Bi₂SiO₅ heterojunction photocatalysts exhibited higher photocatalytic activity than α-Bi₂O₃ on the degradation of organic pollutants under simulated sunlight irradiation. The enhanced photocatalytic activity could be ascribed to the larger specific surface area, the larger contact angle, the formation of β-Bi₂O₃ and construction of p-n heterojunction. More importantly, the phase transition mechanism of Bi₂O₃ in Bi₂O₃/Bi₂SiO₅ heterojunction photocatalyst was proposed, which is significant for the theoretical study and application of photocatalytic materials.

在这项工作中，Bi ₂ O ₃ / Bi ₂ SiO ₅ pn异质结光催化剂通过以Bi（NO ₃）₃和纳米SiO ₂为前体的简便的一步合成成功制备。利用SiO2含量的增加₂，α-Bi系₂ ö ₃逐渐转移到β-Bi系₂ ö _3，以及Bi ₂ ö ₃ /铋₂的SiO ₅同时获得pn异质结。所制备的样品通过X射线衍射，扫描电子显微镜（SEM），能量色散光谱（EDS），透射电子显微镜（TEM），X射线光电子能谱（XPS），紫外可见漫反射光谱（DRS）进行了系统表征）。铋₂ ö ₃ /铋₂的SiO ₅异质结的光催化剂比α-Bi系显示出较高的光催化活性₂ ö ₃上模拟太阳光照射下的有机污染物的降解。增强的光催化活性可能归因于较大的比表面积，更大的接触角，形成β-Bi系₂ ö ₃和pn异质结的构建。更重要的是，提出了Bi ₂ O ₃在Bi ₂ O ₃ / Bi ₂ SiO ₅异质结光催化剂中的相变机理，对于光催化材料的理论研究和应用具有重要意义。