多酸用于可在晴雨天发电的双功能染料敏化太阳能电池的研究

The all-round sustainable development of renewable energy is the important content of the 13th Five-Year plan of China. Solar cell technology has become the major breakthrough of the science and technology in China. It is one of the important research topics to develop Dye-sensitized Solar Cells (DSSC) with high efficiency and low cost to promote the all-round sustainable development of solar energy. At present, the conventional DSSC can only work in the sunlight, the efficiency of which is almost zero under the extreme conditions especially in the rainy days, so it has more development prospects to develop the battery materials with low cost and high output for generating electricity in the rainy days. Polyoxometalates (POMs), contain a lot of delocalized electrons in their polyoxoanion structures with high electronegativity, which may form the electric double layer with the cations and anions in the rain through the Lewis acid-base electrostatic interactions to generate the electrical signals in the charging and discharging processes, finally producing the continuous current with the continuous raindrops. Simultaneously, POMs have good electronic transmission ability, thermal stability, acid-base stability, adjustable into the hydrophobic materials, and low production cost, which are beneficial for the POMs films to be assembled to the back of the photoanodes or the counter electrodes of the DSSC to achieve the electricity generation in rainy days. In the project, POMs are firstly used in DSSC to generate electricity in rainy days, and used as the low cost counter electrodes to make the bifunctional DSSC simultaneously work at both the sunny and rainy days. It will provide the new growth point for the application of POMs chemistry, and be of great significance for the development and utilization of solar energy and the industrialization of solar cells.

可再生能源的全面可持续发展是我国“十三五”规划的重点内容，太阳能电池技术已成为我国重点突破的科学技术，开发高效低成本染料敏化太阳能电池（DSSC）是促进太阳能全面可持续发展的重要研究课题之一。目前，传统DSSC仅能在有光照射时工作，极端条件下尤其是雨天效率几乎为零，因此开发低成本高输出可在雨天发电的电池材料更具发展前景。多酸，由于其多阴离子结构中含有大量离域电子，具有较高电负性，与雨滴中阴阳离子通过静电相互作用形成双电层，在充放电过程中产生电信号，随着雨滴持续滴落进而产生持续电流。同时多酸具有良好的电子传输能力，热稳定性，酸碱稳定性，可被调变成疏水材料，制备成本较低，有利于组装在电池光阳极或对电极背面实现雨天发电。本课题首次将多酸用于DSSC的雨天发电，并以多酸为低成本对电极构筑晴雨天同时发电的双功能DSSC，将为多酸的应用研究找到新的生长点，对太阳能开发利用与电池走向工业化具有重要意义。

传统太阳能电池仅能在有光照射时工作，极端条件下尤其是雨天效率几乎为零，本项目首次将多酸用于雨天发电，并以多酸为低成本对电极构筑晴雨天同时发电的双功能染料敏化太阳能电池（DSSC），对太阳能开发利用与电池走向工业化具有重要意义。本项目在执行期内发表论文24篇，JCR大类一区8篇，培养硕士13人，博士生4人，开展的主要研究工作如下：首先，我们开发了一种多酸/乙基纤维素复合膜，能同时将风、光、雨等多种低值全天候环境能源转化为电能。最佳的Mo72Cr30/乙基纤维素复合膜在模拟太阳光下的光电响应为176.3 μA W-1，风速为10 m s-1时的平均输出功率为4.48 μW m-2，雨滴滴速为7 mL min-1时的平均输出功率为0.25 μW m-2，太阳光与风、太阳光与雨滴、风与雨滴同时驱动的输出功率密度分别为6.32 μW m-2，0.54 μW m-2和8.71 μW m-2。同时受到太阳光、风和雨滴的驱动，它的平均输出功率密度为17.7μW m-2，其长期耐久性是单独风和雨滴条件的4倍和70倍。同时开展了多酸在DSSC对电极中的系列研究，我们开发了钒取代多酸修饰的缺陷态MoS2，采用各向异性集成策略诱导合成多中心NiFeCoW@NC双功能电催化剂，合成了Keggin型多酸/硫尖晶石八面体异质结构催化剂，多酸衍生的多组分X/W2C@X, N-C纳米电催化剂，超晶格P2Mo18/MoS2@C纳米材料等系列对电极材料用于DSSC，效率最高达到8.85%，优于Pt电极。