联系我们  |  网站地图  |  English   |  移动版  |  中国科学院 |ARP
站内搜索:
首页 简介 管理部门 科研部门 支撑部门 研究队伍 科研成果 成果转化 研究生教育 党建与创新文化 科普 信息公开 办公内网
科技信息
Low-cost wearables manuf...
Researchers develop 3-D-...
硫化钴能用来制作超级电容
青岛能源所在石墨炔能源存...
二维非铅钙钛矿动力学机理...
Scientists fine-tune sys...
Amorphous diamond synthe...
化学耦合的硫化镍和碳空心...
全无机钙钛矿光电探测器动...
科研人员提出纳米催化医学...
Newly-discovered semicon...
Molecular nanoparticles ...
碳纳米点固态高效发光新方法
基于甲胺气体的钙钛矿薄膜...
新型镁电池可使储能技术更...
现在位置:首页>新闻动态>科技信息
Researchers create single-crystal perovskite solar cells
2017-09-01 09:17:54 | 编辑: | 【 【打印】【关闭】

Single crystalline CH3NH3PbI3 self-grown on FTO/TiO2 substrate. (a) Schematic self-growth via temperature gradient and capillary effect; (b) cross-sectional SEM image of CH3NH3PbI3 on FTO/TiO2; (c) high resolution TEM image of single crystalline CH3NH3PbI3. Credit: Science China Press

  Photovoltaic conversion is regarded as the ultimate solution to the growing demand for energy, yet traditional silicon-based solar cells are expensive to produce, and production itself involves intensive energy consumption. Emerging hybrid organic-inorganic solar cells based on perovskite CH3NH3PbI3, on the other hand, are not only inexpensive to process but also flexible, and thus are widely pursued as one of the most promising next-generation photovoltaic conversion technologies.

  Since first reported in 2009, the photovoltaic conversion efficiency of perovskite solar cells has increased spectacularly from 3.81 percent to 22.1 percent in just seven years, and this unprecedented rise has fueled worldwide pursuit for new efficiency records. Nevertheless, in the last two years, the pace of perovskite solar cell efficiency gains has slowed considerably despite the distance from the projected theoretical limit of 31 percent. Therefore, researchers are exploring new strategies to further enhance perovskite solar cell performance.

  The current perovskite solar cells are based on polycrystalline CH3NH3PbI3 films, and thus inevitably have many defects in grains and grain boundaries that affect the device performance. Researchers have made efforts to produce bulk CH3NH3PbI3 crystals that exhibit exceptional photovoltaic properties such as long diffusion length and lifetime of photogenerated charge carriers, though the integration of bulk crystal into the perovskite solar cell architecture has proved challenging.

  Now, a team of Chinese and U.S. scientists led by Profs. Jiangyu Li and Jinjin Zhao has successfully grown single-crystalline CH3NH3PbI3 film directly on electron-collecting FTO/TiO2 substrate, as shown in Fig. 1. They took advantage of temperature gradient and the capillary effect during the growth process, enabling them to produce high-quality single crystalline film tightly integrated on FTO/TiO2. This proves critical, as FTO/TiO2 is the most widely used electron-collecting substrate for perovskite solar cells, making subsequent device fabrication straightforward.

  Indeed, the single crystalline CH3NH3PbI3 film shows excellent photovoltaic properties. Measured directly on an FTO glass substrate with poor electron extraction, the time-resolved photoluminescence has much longer carrier lifetime in single crystalline CH3NH3PbI3 film compared to polycrystalline film, as seen in Fig. 2(a). When a TiO2 electron-collecting layer is added to the FTO glass, then the charge carrier lifetime drops substantially, thanks to efficient electron extraction at the TiO2/perovskite interface. As a result, the device exhibits photovoltaic conversion efficiency of 8.78 percent, the highest reported to date for a single crystalline perovskite solar cells. The team says that the system has much room for improvement, and with continuous optimization of materials and devices, they believe that the single crystalline perovskite solar cells will rival their polycrystalline counterparts in the foreseeable future.

 

Photo-carrier properties and photovoltaic performance of single crystalline and polycrystalline CH3NH3PbI3. (a) time-resolved photoluminescence shows longer charge lifetime in single crystalline film and efficient charge collection at the interface with FTO/TiO2 substrate; and (b) current density-voltage curve shows a photovoltaic efficiency of 8.78 percent. Credit: Science China Press 

  Explore further: Semi-transparent perovskite solar cells for solar windows 

  More information: Jinjin Zhao et al. Single crystalline CH3NH3PbI3 self-grown on FTO/TiO 2 substrate for high efficiency perovskite solar cells, Science Bulletin (2017). DOI: 10.1016/j.scib.2017.08.022 

  Provided by: Science China Press 

版权所有 中国科学院上海硅酸盐研究所 沪ICP备05005480号
长宁园区地址:上海市长宁区定西路1295号 电话:86-21-52412990 传真:86-21-52413903 邮编:200050
嘉定园区地址:上海市嘉定区和硕路585号  电话:86-21-69906002 传真:86-21-69906700 邮编:201899