期刊
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
卷 13, 期 9, 页码 3788-3794出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/c0cp02728f
关键词
-
资金
- National Science Foundation [5077078]
- National Key Scientific Program [2007CB936700]
- CAS [KGCX2-YW-326]
- Key Scientific and Technological Program of Jilin Province [10ZDGG012]
In solvent-free ionic liquid electrolytes for efficient dye-sensitized solar cells, iodide and non-iodide melts are ordinarily blended in order to attain a high dynamic fluidity and thereby meet a fast mass transport of electroactive species. This common tactic could bring forth a prominent impact of various anions on cell efficiency by altering photocurrent and/or photovoltage. Herein we report evident effects of the dicyanamide versus tetracyanoborate anion on the energetics of titania conduction band edge and the kinetics of multi-channel charge-transfer reactions in cells employing a high absorption coefficient ruthenium sensitizer C106. A slightly shorter photoluminescence lifetime of C106 grafted on alumina is probed for the tetracyanoborate-based reference cell with respect to the dicyanamide counterpart. However, owing to a more favourable thermodynamic driving force of similar to 90 meV, the tetracyanoborate anion prompts an almost 3-fold faster electron injection from the excited-state dye to titania than dicyanamide, leading to a higher charge separation yield, which is in good agreement with an almost indistinguishable ratio of external quantum efficiency enhancement in the whole spectral response region. Compared to tetracyanoborate, the presence of dicyanamide at the titania/electrolyte interface evokes a 27-fold smaller interfacial electron exchange rate (K) with triiodide, accounting for the open-circuit photovoltage variation observed in current-voltage measurements.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据