离子液体在有机光电转换器件中的应用研究进展

一基金项目:

浙江省自然科学基金(LY１４F０４０００３)一李博:男,１９７５年生,博士,副教授,主要从事有机光电器件及光电检测方面的研究一E-mail :libo＠z j ut．edu．cn 离子液体在有机光电转换器件中的应用研究进展

李一博,徐晓婷,郑雪晴(浙江工业大学理学院,杭州３１００２３)

摘要一一近年来,离子液体因具有不易挥发二性质稳定二透光性好二导电率高二可设计性,以及易于在界面处形成双电层等物理化学性质,而展现出广阔的应用潜力和前景,逐渐成为国际科学研究的前沿和热点之一.其中,将离子液体应用于染料敏化太阳能

电池(D y e-sensitized solar cells ,DSSCs )

二钙钛矿太阳能电池和有机光电探测器等有机光电转换器件的研究备受关注.在有机光电转换器件中,离子液体在染料敏化太阳能电池方面的应用最为广泛且完善.高效DSSCs 主要是基于有机溶剂的液态电解质结,但有机溶剂在带来较高光电转换效率的同时,其本身存在的易挥发汽化二光热稳定性差等缺点,导致DSSCs 的器件寿命与长期稳定性受到影响,离子液体的引入能有效解决以上问题.此外,离子液体还以电子传输层以及界面修饰层的形式引入,具有高电荷迁移率二低功函数以及高稳定性等优点,能在一定程度上改善器件的短路电流二填充因子和光电转换效率等.因此,离子液体成为在DSSCs 的实际应用中兼具性价比高二封装难度低二性能好二稳定性高四大优点的辅助材料.在钙钛矿太阳能电池方面,离子液体的低功函数和高电子迁移率以及一些特殊性质如钝化反应二黏度效应等,都能够实现对电子萃取率二电荷转移电阻二钙钛矿结晶情况等方面的控制以满足实际设计要求,进而有助于钙钛矿太阳能电池的光电转换效率二填充因子等性能指标不同程度的提升.在有机光电探测器方面,引入的离子液体能促使在与之接触的界面处形成双电层,双电层的形成及离子液体的高导电率使得入射光不必照射有机光电探测器上下电极的重叠区域仍旧可以产生较大的光电流输出,从而可以有效摆脱有机光电探测器对电极材料透光性要求的局限性.同时双电层的形成还将促进有机光电探测器工作层中的电荷分离,进一步提高有机光电探测器的响应率.

本文主要从染料敏化太阳能电池二钙钛矿太阳能电池二有机光电探测器三个方面,综述了离子液体在有机光电转换器件中的国内外应用研究进展,就离子液体对提升有机光电转换效率及其实现器件新功能的工作机理进行了详细分析,并对其未来的应用研究方向进行了展望,为今后进一步设计出更适合有机光电转换领域应用的离子液体提供参考.

关键词一一离子液体一光电转换器件一有机一太阳能电池一光电探测器

中图分类号:TB３２２一一文献标识码:A一一DOI :１０.１１８９６/j ．

issn .１００５-０２３X .２０１８.２３.０１３Pro g ress in the A pp lication of Ionic Li q uids in Or g anic Photoelectric Conversion Devices

LI Bo ,XU Xiaotin g ,ZHENG Xue q in g (Colle g e of Science ,Zhe j ian g Universit y of Technolo gy ,Han g zhou ３１００２３)

Abstract 一一In recent y ears ,ionic li q uids have shown wide a pp lication p otential and p ros p ects because of their p h y sical and chemical p ro p erties ,such as non-volatile ,stabilit y of p ro p erties ,favorable transmittance ,hi g h conductivit y ,desi g nabilit y ,and eas y to form electric double la y ers at the interface．Accordin g l y ,ionic li q uids have g raduall y become one of the frontier and hot s p ots in in-ternational scientific research．Amon g them ,the a pp lications of ionic li q uids in or g anic o p toelectronic conversion devices ,includin g d y e-sensitized solar cells ,p erovskite solar cells and or g anic p hotodetectors have attracted numerous attention over the world．In the or g anic p hotoelectric conversion devices ,the a pp lication of ionic li q uids in d y e-sensitized solar cells is the most extensive

and p erfect．The hi g h efficienc y of d y e-sensitized solar cells is p rimaril y de p ended on li q uid electrol y te j unctions in or g anic solvents．Nevertheless ,the hi g h p hotoelectric conversion efficienc y benefited from or g anic solvents is usuall y accom p anied b y volatile va p oriza-tion ,p oor p hotothermal stabilit y ,which badl y affected the lifetime and lon g -term stabilit y of d y e-sensitized solar cells devices．While the introduction of ionic li q uids can effectivel y solve these p roblems．In addition ,ionic li q uids are introduced in the form of electron trans p ort la y ers and interfacial modification la y ers ,brin g in g the advanta g es of hi g h char g e mobilit y ,low p ower function and hi g h sta-bilit y ,which contribute to im p rovin g the short-circuit current ,fillin g factor and p hotoelectric conversion efficienc y to a certain extent．As a result ,ionic li q uids have been reco g nized as the auxiliar y materials with hi g h cost p erformance ratio ,low enca p sulation difficul-t y ,excellent p erformance and g ood stabilit y in p ractical a pp lication of d y e-sensitized solar cells．In p erovskite solar cells ,the low p ower function and hi g h electron mobilit y of ionic li q uids and some s p ecial p ro p erties like p assivation reaction ,viscosit y effect can realize the control of electron extraction rate ,char g e transfer resistance ,p erovskite cr y stallization ,so as to meet the desi g n re q uire-ments in p ractice ,and further hel p to im p rove the p hotoelectric conversion efficienc y and fillin g factor of p erovskite solar cells．Re-四６１１４四材料导报A :综述篇一一２０１８年１２月(A )

第３２卷第１２期万方数据