光电协同原理与新型波纹板式液膜反应器的结构优化

New photoelectro-catalysis technology is capable of completely oxidizing organic pollutants without causing secondary pollutions by using visible light illumination. Therefore it has great potential applications in efficient large scale wastewater treatment, air purification and so on. Study of the scientific principles that can be used to guide the design and operation of efficient photoelectron-catalytic reactors is a critical step to eventually make the potentials of photoelectron-catalysis technology a reality. The objective of the proposed project is to experimentally study new photoelectrocatalytic systems that combines the design concepts in liquid film photoelectrocatalytic reactors and corrugated plate photocatalytic reactors, understand the physical and chemical processes in the systems, and mathematically express them. Through the structure of the corrugated plate reactor design, optimization and modeling, by adjusting the liquid film thickness and surface area, the light scattering, refraction, transmission effect will be enhanced, and the efficiency of transmission and absorption of light will be improved. Through the synergy effect of photo and electric field, the separation of photo-induced electrons and holes will be promoted and the quantum efficiency will be improved. Through adopting ion-doped TiO2, and narrow band gap semiconductors, the photo electrode with visible light responsibility will be released. The dynamics equantions and mechanism of photoelectrocatalysis process under this new reactor will be established and explored, by through optimization and fitting of reaction parameters. Finally, the energy utilization efficiency of photoelectrocatalysis will be greatly increased, by all the aspects of study. This research will provide new ideas for efficient photoelectro-catalysis system and promote the large scale applications in water and air pollution control and other oxidation needs.

新型光电协同催化技术具有深度氧化矿化能力，可以利用太阳光将有机污染物彻底降解，具有无污染，高效能的特点，在污水处理、空气净化等领域有着极其重要的应用前景。构筑高效太阳能转化的光电催化反应器系统是光催化推向实际应用的关键内容之一。本课题拟通过光电协同液膜式反应器与波纹板式反应器结合，实现在波纹板反应器上的高效光电催化转化。通过波纹板式反应器的结构设计、优化及模型化，调节液膜厚度及表面积，加强光的散射、折射、透射效应，提高光的传递与吸收效率；通过光电协同效应促进光生电子-空穴高效分离，提高量子效率；通过采用离子掺杂的TiO2、窄带隙半导体等光电极方式实现对可见光的响应；通过反应参数的优化拟合，建立动力学方程，探索在该反应器下光电催化过程机理，最终实现光电协同催化能量利用效率的大幅提高。项目的实施为光电协同催化反应器设计理论问题提供新思路，可促进光电催化实用化的发展。

光催化是将太阳能转化化学能的过程，具有低成本、无污染的优点，在分解水制氢、降解污染物等方面有广阔的应用前景，对于从根本上解决能源、环境等问题具有重要意义。因而，开发新型可见光响应光催化剂是迫切需要的。本项目在国家自然科学基金（编号21476161）的资助下，在新型光催化材料的设计合成与光催化及光电催化性能的研究方面取得了一系列满意的成果。.本项目从具有π-π共轭结构的光催化材料出发，设计合成了基于g-C3N4纳米片包覆的核壳结构催化剂CdS@g-C3N4、AgI@g-C3N4、AgBr@g-C3N4、Ag2CO3@g-C3N4、BiVO4@g-C3N4和Ag2Mo2O7@g-C3N4，然后拓展到Ag2CO3@PANI核壳结构催化剂。通过一系列表征手段对催化剂晶型结构、形貌、尺寸以及光催化活性和稳定性提高机理进行了系统研究。利用光电化学、光谱学及活性物种捕获等方法，对g-C3N4基复合光催化材料的传导光生电荷的能力和主要活性物种进行了表征，揭示了g-C3N4和PANI提高CdS、AgI及Ag2CO3等催化剂活性和稳定性的机理。研究结果表明，AgI@g-C3N4 (5wt.%)、AgBr@g-C3N4(7 wt.%)、Ag2CO3@g-C3N4(5 wt.%)及Ag2CO3@PAN(3 wt.%)可见光降解染料活性分别比单体提高33.8%、46.0%、41.0%和47.0%；催化剂循环使用5次后，稳定性分别提高2.5、3.9、9.1和14.1倍。同时，复合催化剂对双酚A及苯酚也表现出高的光催化活性，其中Ag2CO3@PANI(3 wt.%)活性最高，40 min可将10 ppm的苯酚降解95.4%。催化剂体现了一定的深度处理实际废水的能力，可见光下反应150 min，可将焦化废水COD由初始值92.0 mg/L降低至18.7 mg/L，COD去除率为79.7%。该工作为深入研究具有π-π共轭结构复合材料提供了新的研究思路。.此外在上述研究的基础上，对提高新型铋系光催化材料的可见光响应进行了探索，利用贵金属纳米颗粒的等离子体共振效应以及光散射效应协同提高铋系光催化剂在可见光下的光催化活性。制备了Cu2O NPs/Bi2O2CO3、Ag@AgBr/Bi2O2CO3、Ag@AgCl/ Bi2O2CO3和CQDs/ Bi2O2CO3等复合光催化剂。制备的新型复合光催化剂在可见光