新型AgBr/GO复合催化剂的制备及其可见光催化还原CO2性能的初步研究

 采用液相合成法，在十三烷基三甲基溴化铵（CTAB）辅助下制备具有可见光效应的AgBr/GO复合材料，并考察其在可见光下催化还原CO₂制备碳氢化合物的可行性及催化性能。XRD和TEM结果表明：AgBr纳米颗粒均匀地分散在GO载体表面，有利于光诱导下产生的电荷在AgBr与GO界面间的有效传递。可见光照射下，AgBr/GO复合催化剂还原CO₂生成的甲烷、甲醇、CO和乙醇的产量分别是106.11、64.20、26.53和10.96 μmol·g^-1，明显高于AgBr的催化活性。AgBr/GO在重复使用5次后其光催化还原CO₂的活性基本保持不变，因此AgBr/GO是一种高效的、光化学性质稳定的催化剂。

Preparation and Photocatalytic Reduction of CO_2 Using Novel AgBr/GO Nanocomposite Catalyst under Visible Light

In this work, the AgBr/GO (graphite oxide) nanocomposite catalysts were prepared by the deposition precipitation method in the presence of cetyltrimethylammonium bromide (CTAB), and their photocatalytic activities were evaluated by the reduction yield in the presence of CO₂ and water under visible light (λ> 420 nm). The results of X-ray diffraction (XRD) and scanning electron microscopy (SEM) showed that AgBr nanoparticles were well dispersed on the surface of GO supporter, which is beneficial to the transfer of photoexcited electrons from the conduction band of well dispersed AgBr to that of GO. The AgBr/GO nanocomposite had relatively high reduction yields under visible light irradiation for 5 h, with a methane yield of 106.11, methanol yield of 64.20, CO yield of 26.53, and ethanol yield of 10.96 μmol·g^-1, respectively. It was obvious that the catalytic activity of AgBr/GO was higher than that of AgBr. In addition, it was found that AgBr/GO photocatalyst was stable in the repeated uses under visible light. The total yields of the photocatalytic products and stability on AgBr/GO after the 5 repeated uses almost remained the same. Therefore, the AgBr/GO nanocomposite is an effective and stable visible light driven photocatalyst for CO₂ photoreduction.