Performance improvement of MEH-PPV:PCBM solar cells using bathocuproine and bathophenanthroline as the buffer layers

doi:10.1088/1674-1056/20/6/068801

Abstract In this work, bathocuproine (BCP) and bathophenanthroline (Bphen), commonly used in small-molecule organic solar cells (OSCs), are adopted as the buffer layers to improve the performance of the polymer solar cells (PSCs) based on poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene) (MEH-PPV): [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM) bulk heterojunction. By inserting BCP or Bphen between the active layer and the top cathode, all the performance parameters are dramatically improved. The power conversion efficiency is increased by about 70% and 120% with 5-nm BCP and 12-nm Bphen layers, respectively, when compared with that of the devices without any buffer layer. The performance enhancement is attributed to BCP or Bphen (i) increasing the optical field, and hence the absorption in the active layer, (ii) effectively blocking the excitons generated in MEH-PPV from quenching at organic/aluminum (Al) interface due to the large band-gap of BCP or Bphen, which results in a significant reduction in series resistance (R_s), and (iii) preventing damage to the active layer during the metal deposition. Compared with the traditional device using LiF as the buffer layer, the BCP-based devices show a comparable efficiency, while the Bphen-based devices show a much larger efficiency. This is due to the higher electron mobility in Bphen than that in BCP, which facilitates the electron transport and extraction through the buffer layer to the cathode.

Keywords: polymer solar cells bathocuproine bathophenanthroline buffer layer

Received: 29 November 2010
Revised: 13 January 2011
Accepted manuscript online:

PACS:	88.40.jr	(Organic photovoltaics)
	71.20.Rv	(Polymers and organic compounds)
	79.60.Jv	(Interfaces; heterostructures; nanostructures)

Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 60978060, 10804006, and 10974013), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20090009110027), the Research Fund for the Youth Scholars of the Doctoral Program of Higher Education, China (Grant No. 20070004031), the Beijing Municipal Natural Science Foundation of China (Grant No. 1102028), the Beijing Municipal Science & Technology Commission of China (Grant No. Z090803044009001), the National Basic Research Program of China (Grant No. 2010CB327705), and the International Science and Technology Cooperation Program (Grant No. 2008DFA61420).

Cite this article:

Liu Xiao-Dong(刘晓东), Zhao Su-Ling (赵谡玲), Xu Zheng(徐征), Zhang Fu-Jun(张福俊), Zhang Tian-Hui(张天慧), Gong Wei(龚伟), Yan Guang(闫光), Kong Chao(孔超), Wang Yong-Sheng(王永生), and Xu Xu-Rong(徐叙瑢) Performance improvement of MEH-PPV:PCBM solar cells using bathocuproine and bathophenanthroline as the buffer layers 2011 Chin. Phys. B 20 068801

[1]	Yu G, Gao J, Hummelen J C, Wudl F and Heeger A J 1995 Science 270 1789
[2]	Reyes-Reyes M, Kim K and Carroll D L 2005 Appl. Phys. Lett. 87 083506
[3]	Kim J Y, Lee K, Coates N E, Moses D, Nguyen T Q, Dante M and Heeger A J 2007 Science 317 222
[4]	Dennler G, Scharber M C and Brabec C J 2009 Adv. Mater. 21 1323
[5]	Chen H Y, Hou J H, Zhang S Q, Liang Y Y, Yang G W, Yang Y, Yu L P, Wu Y and Li G 2009 Nature Photon. 3 649
[6]	Liang Y Y, Xu Z, Xia J B, Tsai S T, Wu Y, Li G, Ray C and Yu L P 2010 Adv. Mater. 22 E135
[7]	Li G, Chu C W, Shrotriya V, Huang J and Yang Y 2006 Appl. Phys. Lett. 88 253503
[8]	Song Q L, Li F Y, Yang H, Wu H R, Wang X Z, Zhou W, Zhao J M, Ding X M, Huang C H and Hou X Y 2005 Chem. Phys. Lett. 416 42
[9]	Kang B, Tan L W and Silva S R P 2008 Appl. Phys. Lett. 93 133302
[10]	Yoo I, Lee M, Lee C, Kim D W, Moon I S and Hwang D H 2005 Synth. Met. 153 97
[11]	Tao C, Ruan S P, Xie G H, Kong X Z, Shen L, Meng F X, Liu C X, Zhang X D, Dong W and Chen W Y 2009 Appl. Phys. Lett. 94 043311
[12]	Brabec C J, Shaheen S E, Winder C, Sariciftci N S and Denk P 2002 Appl. Phys. Lett. 80 1288
[13]	Kim M S, Kang M G, Guo L J and Kim J 2008 Appl. Phys. Lett. 92 133301
[14]	Peumans P and Forrest S R 2001 Appl. Phys. Lett. 79 126
[15]	Chan M Y, Lee C S, Lai S L, Fung M K, Wong F L, Sun H Y, Lau K M and Lee S T 2006 J. Appl. Phys. 100 094506
[16]	Zhao D W, Liu P, Sun X W, Tan S T, Ke L and Kyaw A K K 2009 Appl. Phys. Lett. 95 153304
[17]	Wu Z X, Wang L D, Lei G T and Qiu Y 2005 J. Appl. Phys. 97 103105
[18]	Liu Z T, Kwong C Y, Cheung C H, Djurivsi'c A B, Chan Y and Chui P C 2005 Synth. Met. 150 159
[19]	Liu X D, Xu Z, Zhang F J, Zhao S L, Zhang T H, Gong W, Song J L, Kong C, Yan G and Xu X R 2010 Chin. Phys. B 19 118601
[20]	Peumans P, Yakimov A and Forrest S R 2003 J. Appl. Phys. 93 3693
[21]	Wang N N, Yu J S, Zang Y, Huang J and Jiang Y D 2010 Sol. Energy Mater. Sol. Cells 94 263
[22]	Zhang F, Ceder M and Inganäs O 2007 Adv. Mater. 19 1835
[23]	Ichikawa M, Amagai J, Horiba Y, Koyama T and Taniguchi Y 2003 J. Appl. Phys. 94 7796
[24]	Naka S, Okada H, Onnagawa H and Tsutsui T 2000 Appl. Phys. Lett. 76 197

[1]	Influence of the lattice parameter of the AlN buffer layer on the stress state of GaN film grown on (111) Si Zhen-Zhuo Zhang(张臻琢), Jing Yang(杨静), De-Gang Zhao(赵德刚), Feng Liang(梁锋), Ping Chen(陈平), and Zong-Shun Liu(刘宗顺). Chin. Phys. B, 2023, 32(2): 028101.
[2]	Tetraalkyl-substituted zinc phthalocyanines used as anode buffer layers for organic light-emitting diodes Qian Chen(陈潜), Songhe Yang(杨松鹤), Lei Dong(董磊), Siyuan Cai(蔡思源), Jiaju Xu(许家驹), Zongxiang Xu(许宗祥). Chin. Phys. B, 2020, 29(1): 017302.
[3]	Insight into band alignment of Zn(O,S)/CZTSe solar cell by simulation Zhen-Wu Jiang(姜振武), Shou-Shuai Gao(高守帅), Si-Yu Wang(王思宇), Dong-Xiao Wang(王东潇), Peng Gao(高鹏), Qiang Sun(孙强), Zhi-Qiang Zhou(周志强), Wei Liu(刘玮), Yun Sun(孙云), Yi Zhang(张毅). Chin. Phys. B, 2019, 28(4): 048801.
[4]	Heat transfer of liquid metal alloy on copper plate deposited with film of different surface free energy Huilong Yan(闫慧龙), Jinliang Yan(闫金良), Gang Zhao(赵刚). Chin. Phys. B, 2019, 28(11): 114401.
[5]	Improvement of electro-optic performances in white organic light emitting diodes with color stability by buffer layer and multiple dopants structure Zhi-Qi Kou(寇志起), Yu Tang(唐宇), Li-Ping Yang(杨丽萍), Fei-Yu Yang(杨飞宇), Wen-Jun Guo(郭文军). Chin. Phys. B, 2018, 27(10): 107801.
[6]	Inverted organic solar cells with solvothermal synthesized vanadium-doped TiO₂ thin films as efficient electron transport layer Mehdi Ahmadi, Sajjad Rashidi Dafeh, Samaneh Ghazanfarpour, Mohammad Khanzadeh. Chin. Phys. B, 2017, 26(9): 097203.
[7]	Fullerene solar cells with cholesteric liquid crystal doping Lulu Jiang(姜璐璐), Yurong Jiang(蒋玉荣), Congcong Zhang(张丛丛), Zezhang Chen(陈泽章), Ruiping Qin(秦瑞平), Heng Ma(马恒). Chin. Phys. B, 2016, 25(9): 098401.
[8]	Inverted polymer solar cells with employing of electrochemical-anodizing synthesized TiO₂ nanotubes Mehdi Ahmadi, Sajjad Rashidi Dafeh, Hamed Fatehy. Chin. Phys. B, 2016, 25(4): 047201.
[9]	Improved performance of polymer solar cells by using inorganic, organic, and doped cathode buffer layers Taohong Wang(王桃红), Changbo Chen(陈长博), Kunping Guo(郭坤平), Guo Chen(陈果), Tao Xu(徐韬), Bin Wei(魏斌). Chin. Phys. B, 2016, 25(3): 038402.
[10]	Improved performance of microcrystalline silicon solar cell with graded-band-gap silicon oxide buffer layer Shi Zhen-Liang (史振亮), Ji Yun (季云), Yu Wei (于威), Yang Yan-Bin (杨彦斌), Cong Ri-Dong (丛日东), Chen Ying-Juan (陈英娟), Li Xiao-Wei (李晓苇), Fu Guang-Sheng (傅广生). Chin. Phys. B, 2015, 24(7): 078105.
[11]	The enhancement of 21.2%-power conversion efficiency in polymer photovoltaic cells by using mixed Au nanoparticles with a wide absorption spectrum of 400 nm-1000 nm Hao Jing-Yu (郝敬昱), Xu Ying (徐颖), Zhang Yu-Pei (张玉佩), Chen Shu-Fen (陈淑芬), Li Xing-Ao (李兴鳌), Wang Lian-Hui (汪联辉), Huang Wei (黄维). Chin. Phys. B, 2015, 24(4): 045201.
[12]	Photoactive area modification in bulk heterojunctionorganic solar cells using optimization of electrochemicallysynthesized ZnO nanorods Mehdi Ahmadi, Sajjad Rashidi Dafeh. Chin. Phys. B, 2015, 24(11): 117203.
[13]	Effect of CoSi₂ buffer layer on structure and magnetic properties of Co films grown on Si (001) substrate Hu Bo (胡泊), He Wei (何为), Ye Jun (叶军), Tang Jin (汤进), Syed Sheraz Ahmad, Zhang Xiang-Qun (张向群), Cheng Zhao-Hua (成昭华). Chin. Phys. B, 2015, 24(1): 017502.
[14]	Improved performance of P3HT：PCBM solar cells by both anode modification and short-wavelength energy utilization using Tb(aca)₃phen Zhuo Zu-Liang (卓祖亮), Wang Yong-Sheng (王永生), He Da-Wei (何大伟), Fu Ming (富鸣). Chin. Phys. B, 2014, 23(9): 098802.
[15]	Low-leakage-current AlGaN/GaN HEMTs on Si substrates with partially Mg-doped GaN buffer layer by metal organic chemical vapor deposition Li Ming (黎明), Wang Yong (王勇), Wong Kai-Ming (王凯明), Lau Kei-May (刘纪美). Chin. Phys. B, 2014, 23(3): 038403.

No Suggested Reading articles found!

Viewed

Full text

Abstract

Cited

Metrics
Related Articles

Performance improvement of MEH-PPV:PCBM solar cells using bathocuproine and bathophenanthroline as the buffer layers

Cite this article:

Online attention