摘要
以聚3-己基噻吩(P3HT)为给体材料,富勒烯衍生物(PC61BM)为受体材料,制备了一系列结构为ITO/PEDOT:PSS/P3HT:PC61BM/C60/Al的体异质结光电探测器.研究了120、160、180与200 nm不同光敏层厚度,100、120、130、140与150℃不同退火温度等条件对器件性能的影响,并采用原子力显微镜(AFM)对光敏层形貌进行了分析.研究发现,基于180 nm厚光敏层、150℃退火处理的器件,在-2 V的偏压下550 nm处有最大响应度,为268 mA/W,并且在470~610 nm范围内响应度都超过了200 mA/W;基于180 nm厚光敏层、120℃退火处理的器件有最大线性动态范围,为95 dB.研究表明,适当厚度的光敏层有利于提高光吸收效率与器件的光伏性能;退火处理,可以使光敏层形成均匀的互穿网络结构,进而减小空穴与电子的复合概率,提高器件的光伏性能.
Poly(3-hexylthiophene)(P3HT) with good electronic transmission capacity is one of promising material for organic photodetector. Compared with organic solar cells, the research of photodetector based on P3HT is deficient, especially in how to improve the light absorption efficiency and electronic transmission ability of active layer. Here, bulk heterojunction photodetectors with a structure of ITO/PEDOT:PSS/P3HT:PC61BM/C60/Al were prepared by using P3HT as a donor and fullerene derivative(PC61BM) as an acceptor. The change of active layer thickness plays an important role in the effective transfer of photogenerated charge to the electrode.Although increasing the thickness of active layer can increase the light absorption efficiency, it may also lead to the recombination of electrons and holes in the process of long distance transmission. In addition, annealing condition is the key to the film forming process. Adjusting the annealing temperature can control the self-assembly of active layer, thus obtaining the ideal nano-size phase separation structure and reducing the recombination probability of photoexcitons. Therefore, the active layer thickness in P3HT devices varied at 120, 160, 180 and 200 nm and the devices were annealed at 100, 120, 130, 140 and 150 ℃ in order to probe the effect of these variables on photodetector performance. It was found that the device with a 180-nm thick active layer, after being annealed at 150 ℃, exhibited the maximal responsivity of 268 mA/V at 550 nm and more than 200 mA/W in the wavelengths of 470-610 nm under the bias of-2 V. Furthermore, the same device showed a linear dynamic range of 95 dB after annealing at 120 ℃. Our study demonstrates that the thickness of active layer is of great importance to the light absorption efficiency and the device performance, while the annealing treatment can significantly affect the morphology of active layer, as evidenced by AFM study, which reduces the recombination probability of holes and the electrons and thus improves the photodetector performance.
作者
高诗佳
王鑫
张育林
张赛
乔文强
王植源
Shi-jia Gao;Xin Wang;Yu-lin Zhang;Sai Zhang;Wen-qiang Qiao;Zhi-yuan Wang(State Key Laboratory of Fine Chemicals,Department of Polymer Science&Materials,Dalian University of Technology,Dalian 116024)
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2020年第4期338-345,I0002,共9页
Acta Polymerica Sinica
基金
国家自然科学基金(基金号21474105)
大连市顶尖及领军人才项目(项目号2017RD02)资助.
作者简介
通讯联系人:乔文强,E-mail:wqqiao@dlut.edu.cn;通讯联系人:王植源,wwjoy@dlut.edu.cn。
