| 题名 | 基于多酸的人工光合系统的构筑及性能研究 |
| 作者 | 商新科 |
| 学位类别 | 工程硕士 |
| 答辩日期 | 2014-04 |
| 授予单位 | 中国科学院研究生院 |
| 导师 | 张光晋 |
| 关键词 | 多金属氧酸盐 人工光合作用系统 光解水 氢气 光电响应 |
| 其他题名 | Studies on the Construction and Performance of Polyoxometalate-based Artificial Photosynthetic System |
| 学位专业 | 化学工程 |
| 中文摘要 | 当前，由于传统化石能源煤、石油、天然气等不断消耗，能源资源短缺问题和环境污染问题日益严重，人们迫切需要寻找和开发新的绿色清洁能源。太阳能是取之不尽用之不竭的绿色无污染的清洁能源，因而利用和转换太阳能为我们所需的能源成为解决以上问题的一条途径。通过构筑人工光合作用系统来光催化、光电催化分解水制氢气是把太阳能转化为可储存的化学能很重要的一个方面。而这一过程的可行性取决于所采用的催化材料的性能。 多金属氧酸盐 (多酸，POMs) 是一类新型绿色光电催化材料，它即可以单独作为人工光合作用系统的中心物质，同时也可以与其他材料复合构筑光阳极材料，因此我们首先选择过渡金属Fe、Co、Zn取代的POMs， Na5[FeTiW11O39]?34H2O (TiW11Fe)，Na5[CoTiW11O39]?28H2O (TiW11Co) 以及Na6[ZnTiW11O39]?28H2O (TiW11Zn) 作为研究对象，考察其在均相体系中模拟太阳光光催化产氢活性。同时，将三种过渡金属取代多酸的催化活性与磷钨酸H3PW12O40 (PW12) 进行了对比，实验结果表明三种物质都表现出较好的光催化产氢性能，其产氢活性顺序依次为TiW11Co≈TiW11Zn>TiW11Fe>>PW12。通过实验从热力学以及动力学角度对各物质的光催化活性差异做出了解释。最后，我们提出了在均相体系中的模拟太阳光光催化产氢机理类似于植物光合作用过程的“Z”模型。 另外，我们利用一种多酸偏钨酸铵 ((NH4)6H2W12O40，表示为H2W12)和氧化石墨(GO)、CdS量子点通过层层自组装的方法在导电玻璃上构筑复合物薄膜作为光阳极材料，利用多酸(H2W12)的光催化活性原位还原GO为石墨烯 (rGO)，利用紫外可见吸收光谱以及电化学循环伏安法考察了膜增长的过程，利用XPS、SEM以及AFM等表征手段对薄膜的结构和形貌进行了考察。最后我们考察了复合物薄膜光阳极在模拟太阳光下光电流响应性能并提出机理。 |
| 英文摘要 | Recently, due to the constant consumption of traditional fossil fuels, such as coal, oil and natural gas, we have faced increasingly serious problem with energy resources shortage and environmental pollution, thus it’s an urgent need to find and develop new and green energy. Solar energy is inexhaustible and pollution-free, make full use of solar energy and transfer it to energy that we need is a promising way to solve the problem above. It is a very important aspect to put the solar energy into chemical energy by photocatalytic or photoelectric catalytic decomposition of water into hydrogen through constructing artificial photosynthesis system. The feasibility of this process depends on the performance of the catalytic materials. Polyoxometalate (POMs) is a kind of new green photoelectric catalytic material, it can not only be used separately as central material in the artificial photosynthesis system but also used for combining with other materials to construct photoanode. Thus firstly we studied the photocatalytic activities of three compounds with different transition metal substitution that are Na5[FeTiW11O39]?34H2O (TiW11Fe), Na5[CoTiW11O39]?28H2O (TiW11Co) and Na6[ZnTiW11O39]?28H2O (TiW11Zn) in homogeneous solution under simulated solar light irradiation. At the same time, H3PW12O40 (PW12), was taken as the contrast in homogeneous systems. It was demonstrated that all of the three compounds showed good photocatalytic activity for H2 evolution and the order was as follows: TiW11Co≈TiW11Zn>TiW11Fe>>PW12. The differences of performance on photocatalytic hydrogen evolution was elucidated from the perspective of thermodynamics and kinetics. At last, the mechanism of photocatalytic process was proposed as “Z-scheme” that is simulated as occurred in plant photosynthetic systems. In addition, we combined a kind of POMs ammonium metatungstate ((NH4)6H2W12O40, denoted as H2W12) with GO and CdS quantum dots to form the composite thin films on conducting glass as photoanode material by the layer-by-layer (LbL) self-assembly method, and an in situ photoreduction protocol was adopted to convert GO to rGO due to the photocatalytic activity of H2W12. Uv-vis absorption spectroscopy and cyclic voltammetry were adopted to monitor the growing process of the composite films. XPS, SEM and AFM characterization methods were used to observe the morphology and structure of the composite films. Finally, we examined the photocurrent response performance of the composite films coated photoanode under simulated sunlight irradiation and put forward the proposed mechanism. |
| 语种 | 中文 |
| 公开日期 | 2015-07-08 |
| 内容类型 | 学位论文 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/15574]  |
| 专题 | 过程工程研究所_研究所（批量导入） |
| 推荐引用方式 GB/T 7714 | 商新科. 基于多酸的人工光合系统的构筑及性能研究[D]. 中国科学院研究生院. 2014. |
| 个性服务 |
| 查看访问统计 |
| 相关权益政策 |
| 暂无数据 |
| 收藏/分享 |
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
修改评论