Cu2O-g-C3N4异质结催化剂光催化降解甲基橙

采用水热还原法和高温煅烧法将Cu₂O生长到石墨型氮化碳（g-C₃N₄）表面,制得Cu₂O-g-C₃N₄异质结复合光催化剂。通过XRD、XPS、SEM、TEM、DRS、PL、BET等技术对催化剂进行了表征,研究了Cu₂O-g-C₃N₄降解甲基橙的光催化性能及主要活性物种。实验和表征结果表明： Cu₂O与g-C₃N₄面面接触,两相间化学作用强烈;Cu₂O-g-C₃N₄催化剂能有效利用太阳光,电子-空穴得到有效分离;当n（Cu₂O）∶n（g-C₃N₄）=5∶1时,Cu₂O-g-C₃N₄催化剂的活性最佳,在可见光下反应30 min时,甲基橙降解率达84.1%;Cu₂O-g-C₃N₄具有较好的活性稳定性,重复使用6次,甲基橙降解率降至64.7%;电子-空穴是Cu₂O-g-C₃N₄光催化降解甲基橙的主要活性物种。

Photocatalytic degradation of methyl orange on Cu2O-g-C3N4 heterojunction catalyst

In this study,Cu₂O-g-C₃N₄ heterojunction photocatalysts were prepared by hydrothermal reduction method and high temperature calcination method to grow Cu₂O onto graphitic carbon nitride （g-C₃N₄）surface. The catalysts were characterized by X-ray diffusion （XRD）,X-ray photoelectron spectroscopy （XPS）,scanning electron microscopy （SEM）,transmission electron microscopy （TEM）,diffuse reflection spectrometry （DRS）,photoluminescence spectroscopy （PL）and Brunauer-Emmett-Teller method （BET）. The photocatalytic activity and main active species for methyl orange degradation by Cu₂O-g-C₃N₄ were studied. The experimental results and the characterization results showed that Cu₂O was in contact with the g-C₃N₄ surface and the chemical interaction between the two phases was strong. The Cu₂O-g-C₃N₄ catalyst could effectively use the sunlight and effective electron-hole separation could be achieved. When n（Cu₂O）∶n（g-C₃N₄）=5∶1,the activity of the Cu₂O-g-C₃N₄ catalyst was the best. The degradation rate of methyl orange was 84.1% when the reaction proceeded under visible light for 30 minutes. Cu₂O-g-C₃N₄ had good activity stability;after the Cu₂O-g-C₃N₄ was reused for 6 times,the degradation rate of methyl orange decreased to 64.7%. Additionally,electron-hole was the main active species for photocatalytic degradation of methyl orange by Cu₂O-g-C₃N₄.