Stability enhancement of organic photovoltaic devices utilizing partially reduced graphene oxide as the hole transport layer: nanoscale insight into structural/interfacial properties and aging effects
Stability enhancement of organic photovoltaic devices utilizing partially reduced graphene oxide as the hole transport layer: nanoscale insight into structural/interfacial properties and aging effects
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DOI：
10.1039/c5ra24010g
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发表时间：
2015-12
期刊：
影响因子：
3.9
通讯作者：
B. Paci;G. Kakavelakis;A. Generosi;V. R. Albertini;Jonathan P. Wright;C. Ferrero;Dimitrios Konios;E. Stratakis;E. Kymakis
中科院分区：
文献类型：
--
作者：
B. Paci;G. Kakavelakis;A. Generosi;V. R. Albertini;Jonathan P. Wright;C. Ferrero;Dimitrios Konios;E. Stratakis;E. Kymakis
报道了一种对后制作的体异质结（BHJ）有机光伏（OPV）器件的结构和界面特性的深入研究。结合X射线衍射（XRD）和荧光（XRF）研究揭示了集成器件的纳米级局部结构。对使用氧化石墨烯（GO）作为空穴传输层（HTL）的器件和参考PEDOT：PSS（聚（3，4-亚乙基二氧噻吩）：聚（苯乙烯磺酸盐））器件进行比较研究。空间分辨的同时XRD/XRF测量与纳米分辨率的原始和老化状态的设备的证据发生的形态修改的聚（2，7-咔唑）衍生物（PCDTBT）：富勒烯衍生物（PC 71 BM）的活性层，诱导热还原和太阳能照射。此外，结果表明，具有部分还原的氧化石墨烯（pr-GO）用作HTL的OPV器件表现出与基于PEDOT：PSS的器件类似的光伏特性，但具有显著的耐久性增强。这归因于pr-GO膜对湿气和铟从氧化铟锡（ITO）阳极扩散到光活性层中的保护作用。结果，用pr-GO-HTL制造的器件在20小时内保持其初始功率转换效率的约65%，而参考器件的效率降低到初始值的45%。
A powerful insight into the structural and interfacial properties of post-fabricated bulk heterojunction (BHJ) organic photovoltaic (OPV) devices is reported. The nanoscale local structure of integrated devices is revealed by combined X-ray diffraction (XRD) and fluorescence (XRF) investigations. A comparative study is performed on devices using graphene oxide (GO) as the hole transporting layer (HTL) and reference PEDOT:PSS (poly(3,4 ethylenedioxythiophene):poly(styrenesulfonate)) devices. Spatially resolved simultaneous XRD/XRF measurements with nanometre resolution on pristine and aged states of the devices evidence the occurrence of morphological modifications in the poly(2,7-carbazole) derivative (PCDTBT):fullerene derivative (PC71BM) active layer, induced by thermal reduction and solar illumination. Additionally, the results indicate that OPV devices with partially reduced graphene oxide (pr-GO) used as the HTL, exhibit photovoltaic characteristics similar to the PEDOT:PSS based devices but with a significant durability enhancement. This is attributed to the protecting role of the pr-GO film against humidity and indium diffusion from the Indium Tin Oxide (ITO) anode into the photoactive layer. As a result, the devices fabricated with pr-GO-HTL retain approximately 65% of their initial power conversion efficiency over 20 hours, while the efficiency of the reference devices degrades to 45% of the initial value.