CC/PANI/TiO2复合材料的制备及其光催化性能研究

Synthesis of CC/PANI/TiO2 composite material and its photocatalytic performance

摘要:

先采用原位聚合的方法在碳布上负载聚苯胺,然后利用溶剂热法在制备的碳布/聚苯胺(CC/PANI)复合材料上生长二氧化钛纳米片,得到了可便捷分离的CC/PANI/TiO₂复合光催化材料。通过SEM、XRD、UV、FTIR、XPS等手段对所制备的样品进行了形貌和结构表征,并比较了CC/PANI/TiO₂复合材料和纯TiO₂紫外-可见光条件下催化降解RhB的活性差异,结果表明CC/PANI/TiO₂复合材料具有比TiO₂更优异的光催化活性。光致发光光谱说明CC/PANI/TiO₂复合材料的发光强度比纯TiO₂的弱,有效抑制了光生载流子的复合；瞬态光电流响应和电化学阻抗谱(EIS)证明CC/PANI/TiO₂纳米复合材料更有效促进电子-空穴对分离和提高转移效率；活性物质捕捉实验证实?OH和?O_2^-是复合材料光催化降解RhB过程中的主要活性物质。CC/PANI/TiO₂复合材料循环利用6次后,仍然具有较高的催化活性,显示了其在污水处理领域中的良好应用前景。

Abstract:

Polyaniline was firstly grown on carbon cloth by in-situ polymerization. The final composite material of CC/PANI/ TiO₂ was then successfully synthesized via solvothermal method, during which TiO₂ nanosheets was formed on the prepared carbon cloth/polyaniline (CC/PANI) composite material. The synthesized photocatalysts were characterized using SEM, XRD, UV, FTIR,XPS and so on. The photocatalytic degradation performances of RhB over the prepared CC/PANI/TiO₂ and the pure TiO₂ were compared. The results indicated that CC/PANI/TiO₂ composite material had better photocatalytic activity than TiO₂ under UV-vis irradiation. PL showed that the luminescence intensity of CC/PANI/TiO₂ was much weaker than that of pure TiO₂, which inhibited the electron-hole pair recombination effectively. Transient photocurrent response and EIS curves verified that CC/PANI/TiO₂ catalyst showed more efficient photocarrier separation and transfer efficiency, beneficial to the improvement of photocatalytic activity. The capture of active pieces experiments indicated that the free .OH radicals and ^_.O_2^- radicals were the main active oxidizing species involved in the RhB photoreaction process of CC/PANI/TiO₂. Moreover, CC/PANI/TiO₂ catalyst still had high catalytic activity after 6 times of recycling, showing its good application prospects in the field of sewage treatment.