【作者】 张炜；

【导师】 李珺；

【作者基本信息】 西北大学 ， 无机化学， 2018， 硕士

【摘要】 随着社会的快速发展,工业和农业的生产量大大增加,随之而来的环境污染问题困扰着人类,尤其是水污染问题。因此,如何高效地去除水体中的污染物成为科研工作者的研究热点。由于TiO₂光催化技术可直接利用太阳能,因而它被广泛地运用到水治理中。但TiO₂是宽带半导体,它只能吸收紫外光,不能充分地利用太阳能,而具有共轭离域结构的卟啉/铜卟啉在可见光区有强吸收,它们可以对TiO₂进行敏化,从而增加其对太阳光的吸收率。本论文合成了5,10,15,20-四-（3-乙酯基亚丙氧基）苯基卟啉（H₂P1）和5,10,15,20-四-（3-羧基亚丙氧基）苯基卟啉（H₂P2）两种自由卟啉及它们对应的铜卟啉5,10,15,20-四-（3-乙酯基亚丙氧基）苯基铜卟啉（CuP1）和5,10,15,20-四-（3-羧基亚丙氧基）苯基铜卟啉（CuP2）,并对它们进行了EA、UV-vis、FT-IR、MS和¹H NMR表征,确定了它们的分子组成和结构。通过室温下醇解钛酸正丁基酯得到TiO₂溶胶,将其与所合成的卟啉/铜卟啉在溶剂热条件下反应制得相应的四种卟啉/铜卟啉-TiO₂复合光催化剂:H₂P1-TiO₂、H₂P2-TiO₂、CuP1-TiO₂和CuP2-TiO₂,对所合成的复合光催化剂进行了XRD、SEM、EDS、Mapping、TEM、UV-vis-DRS、FT-IR、XPS、PL和BET表征,证明了卟啉/铜卟啉的成功负载;分别通过光催化降解和还原水中的4-NP实验评价了所制备的复合光催化剂的光催化活性及其稳定性,并对光催化降解4-NP实验中的活性物种进行了检测,探究了实验的反应机理。结果表明:（1）溶剂热反应后的TiO₂和复合光催化剂均暴露了高活性的（001）晶面;（2）实验合成的卟啉/铜卟啉成功地负载在了TiO₂上,且通过Ti-O-C=O键和TiO₂相互作用;（3）卟啉/铜卟啉-TiO₂复合光催化剂具有异质结,有利于光生电子和空穴的传递,使复合光催化剂具有增强的光催化活性;（4）合成的复合光催化剂在降解4-NP中表现出较高的光催化活性,其中CuP2-TiO₂复合光催化剂的性能最优越;（5）光催化降解4-NP实验中的活性物种是h⁺;（6）合成的复合光催化剂可将4-NP高效地加氢还原为4-AP;（7）经过五次循环实验后,复合光催化剂在降解和还原4-NP中仍保持较高的光催化活性,具有良好的稳定性。更多还原

【Abstract】 With the rapid development of science and technology,the production of industry and agriculture has greatly increased,and it has also brought about environmental pollution,especially,water pollution.Therefore,how to efficiently remove pollutants in water has become a research hotspot for researchers.Photocatalytic technology based on TiO₂ can utilize solar energy and widely used in water treatment.However,TiO₂ is a broadband semiconductor,it can only absorb ultraviolet light and cannot fully utilize solar energy.Porphyrins/copper porphyrins with conjugated delocalized structures have strong sbsorption in the visible light region,which can sensitize TiO₂ and increase its the absorptivity of light.In this paper,twokindsoffreeporphyrins5,10,15,20-tetra[3-（ethoxycarbonylpropyleneoxy）phenyl]porphyrin（H₂P1）,5,10,15,20-tetra[3-（carboxylpropyleneoxy）phenyl]porphyrin（H₂P2）and their corresponding copper porphyrins Cu（II）5,10,15,20-tetra[3-（ethoxycarbonylpropyleneoxy）phenyl]porphyrin（CuP1）and Cu（II）5,10,15,20-tetra[3-（carboxylpropyleneoxy）phenyl]porphyrin（CuP2）,were synthesized and characterized by EA,UV-vis,FT-IR,MS and ¹HNMR,and their molecular compositions and structures were determined.The TiO₂ sol was obtained by alcoholysis of n-butyl titanate at room temperature,and the corresponding porphyrin/copper porphyrin-TiO₂ composite photocatalysts（H₂P1-TiO₂,H₂P2-TiO₂,CuP1-TiO₂ and CuP2-TiO₂）were prepared by reacting with the synthesized porphyrins/copper porphyrins under solvothermal conditions.The synthesized composite photocatalysts were characterized by XRD,SEM,TEM,UV-vis-DRS,FT-IR,XPS,PLand BET,which demonstrate the successful loading of porphyrins/copper porphyrins.The photocatalytic activities and stabilities of the prepared composite photocatalysts were evaluated by photocatalytic degradation and reduction 4-NP in water,and the active species in the photocatalytic degradation of 4-NP were tested to explore the reaction mechanism.The results show that:（1）TiO₂ and composite photocatalysts after solvothermal reaction exposed the highly active（001）crystal plane;（2）The experimental synthesized porphyrins/copper porphyrins were successfully loaded on the surface of TiO₂.The porphyrins/copper porphyrins molecules interact with TiO₂ through Ti-O-C=O bond.;（3）The porphyrin/copper porphyri-TiO₂ composite photocatalyst has a heterojunction,which is beneficial to the tranfer of photogenerated electrons and holes,and makes the composite photocatalyst have enhanced photocatalytic activity;（4）The synthesized composite photocatalyst exhibited higher photocatalytic activity in the degradation of 4-NP,in which the CuP2-TiO₂ composite photocatalyst had the best performance;（5）The photocatalystic degradation of active species in the 4-NP experiment is h⁺mainly;（6）The synthesized composite photocatalysts can efficiently hydrogenate 4-NP to 4-AP;（7）After five cycles of experiments,the composite photocatalysts still maintain high photocatalytic activities in degradation and reduction of4-NP,and have high stabilities.更多还原