| 查看: 231 | 回复: 1 | |||
| 当前主题已经存档。 | |||
[交流]
【长春应用化学研究所】Solar cell electrolytes: Into the mix
|
|||
|
Ionic liquid mixtures can be used as solvent-free electrolytes in high-performance dye-sensitized solar cells -------------------------------------------------------------------------------- IntroductionThe electrolytes of high-performance dye-sensitized solar cells (DSCs) have previously contained volatile solvents, which need robust encapsulation if they are to be used outdoors. Now, Michael Grätzel and co-workers from the Swiss Federal Institute of Technology and the Chinese Academy of Sciences in Changchun have developed stable and solvent-free ionic liquid electrolytes through the rational mixing of three solid imidazolium salts1. In the basic set-up for a DSC, an incident photon excites a dye molecule, initiating the transfer of one of its electrons to a porous TiO2 electrode. This leaves behind a 'hole' that must be removed to stop hole–electron recombination, and this is achieved through an iodide electrolyte that reacts with the oxidized dye to form triiodide, which can then diffuse to the cathode. The electrolyte must be highly conductive, a property that is inversely proportional to viscosity. Alkyl-substituted methylimidazolium iodides have previously been demonstrated as electrolytes in DSCs; their viscosity decreases with decreasing substituted alkyl chain length. The least viscous and most conductive of the series at room temperature is 1-propyl-3-methylimidazolium iodide (PMII), but decreasing the alkyl chain — and thus viscosity — any further is not possible because the shorter chain 1-ethyl- and 1-methyl- imidazolium iodides (EMII and DMII) are solids at room temperature. After systematically studying the viscosity, the melting temperature and the conductivity of a series of hydrocarbon-substituted imidazolium iodides, Grätzel and colleagues created two ternary mixtures of EMII, DMII and either 1-allyl-3-methylimidazolium iodide (AMII) or 1-ethyl-3-methylimidazolium tetracyanoborate (EMITCB). The mixtures were liquid at room temperature and displayed the desired high-conducting properties of their constituents. DSC devices were made incorporating the electrolytes, and were stable for over 1,000 hours of testing. The EMII–DMII–EMITCB system displayed an efficiency of 8.2%, setting a benchmark for solvent-free electrolytes. 全文请看： Bai, Y. et al. High-performance dye-sensitized solar cells based on solvent-free electrolytes produced from eutectic melts. Nature Mater. doi: 10.1038/nmat2224 (2008). http://www.nature.com/uidfinder/10.1038/nmat2224 [ Last edited by weihui_cn on 2008-7-15 at 11:23 ] |
回复此楼» 猜你喜欢
南方科技大学招收金属材料方向博士生
已经有23人回复
-
可降解聚酯材料在医疗器械中的应用趋势与创新方向
已经有0人回复
-
有机高分子材料论文润色/翻译怎么收费?
已经有179人回复
-
可降解微球如何提升药物精准治疗效果
已经有0人回复
-
静电纺丝膜分层问题
已经有0人回复
-
什么脱膜剂可以完全清洗干净啊？
已经有2人回复
-
暨南大学化学与材料学院赵宇亮院士正在招博士和博后，方向为生物材料和纳米医学
已经有1人回复
-
可生物降解聚酯正在重塑现代医疗器械
已经有0人回复
-
26届博士申请
已经有1人回复
trixaypm
木虫 (职业作家)
枯藤老树昏虫兼小木虫清洁工
- 应助: 0 (幼儿园)
- 贵宾: 0.02
- 金币: 4160.2
- 红花: 3
- 帖子: 3522
- 在线: 14.2小时
- 虫号: 238318
- 注册: 2006-04-05
- 性别: GG
- 专业: 高分子物理与高分子物理化
2楼2008-07-15 12:47:06