S掺杂BiOBr的制备及其光催化固氮性能研究

以硫脲、五水硝酸铋为前驱体，采用溶剂热法制备出S掺杂BiOBr光催化剂。利用XRD，SEM，XPS，UV-Vis DRS、光电化学性能等对所制备的光催化材料进行了一系列表征。同时，在可见光照射下对S掺杂BiOBr进行光催化固氮性能研究。结果表明：S掺杂BiOBr的晶体结构未发生改变，比表面积增大。同时，形成的氧空位有利于吸附、活化N2分子和促进光生载流子的迁移，进而提高其光催化固氮性能。与BiOBr相比，S掺杂BiOBr的光催化产氨为25.36 mg?L-1?h-1?g-1cat，是BiOBr的4.6倍。最后，经4次循环实验，S掺杂BiOBr催化剂仍保持稳定的固氮效率。

Preparation of S Doped BiOBr Photocatalyst and Its Nitrogen Fixation Performance

A series of S-doped BiOBr photocatalysts were synthesized using thiourea and Bi(NO₃)₃·5H₂O as precursors through solvothermal process, which were characterized by XRD, SEM, XPS, UV-Vis DRS, photoelectric property. Characterization results revealed that the S-doped BiOBr photocatalyst has identical crystal structure, larger specific surface area and higher photo-induced charge migration ability than that of BiOBr photocatalyst. These properties may contribute to adsorb, activateN₂ molecules and enhance the nitrogen photofixation activity. It was also found that the rate of NH⁴⁺ production forN₂ photofixation of S-doped BiOBr could reached~25.54 mg·L^-1 ·h^-1 ·g^-1_cat, which is approximately~4.6 times higher than that of BiOBr. Moreover, after four cycle experiments, the S-doped BiOBr still has high nitrogen fixation efficiency.