Influence of molecular architecture and intermixing on the photovoltaic, morphological and spectroscopic properties of CuPc-C60 heterojunctions

被引:123
作者
Heutz, S [1 ]
Sullivan, P [1 ]
Sanderson, BM [1 ]
Schultes, SM [1 ]
Jones, TS [1 ]
机构
[1] Univ London Imperial Coll Sci Technol & Med, Dept Chem, Ctr Elect Mat & Devices, London SW7 2AZ, England
基金
英国工程与自然科学研究理事会;
关键词
molecular architecture; intermixing; CuPc-C-60; heterojunctions;
D O I
10.1016/j.solmat.2004.02.027
中图分类号
TE [石油、天然气工业]; TK [能源与动力工程];
学科分类号
0807 ; 0820 ;
摘要
The effects of film thickness, codeposition and introduction of exciton-blocking layers are investigated for heterojunction photovoltaic devices based on copper phthalocyanine (CuPc) and fullerene (C-60). Device performance peaks at low film thicknesses and is improved by the introduction of a mixed layer between continuous pure layers at the electrodes. The control afforded by organic molecular beam deposition enables a detailed analysis of the effects of mixed-layer composition on the device performance. The highest efficiency is reached for devices containing 75% CuPc and is further improved in structures containing multiple mixed layers that lead to the creation of a gradient of donor-acceptor compositions. The mixed-layer properties were assessed using atomic force microscopy and electronic absorption spectroscopy. In most cases, amorphous films with intimate molecular mixing are formed, but several exceptions rationalise the efficiencies observed in corresponding devices. Finally, the degradation of the devices under solar illumination highlights the destructive effects of oxygen, which are found to be particularly severe in mixed-layer devices. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:229 / 245
页数:17
相关论文
共 33 条
[1]   Thin film properties and surface morphology of metal free phthalocyanine films grown by organic molecular beam deposition [J].
Bayliss, SM ;
Heutz, S ;
Rumbles, G ;
Jones, TS .
PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 1999, 1 (15) :3673-3676
[2]  
Bayliss SM, 2000, ADV MATER, V12, P202, DOI 10.1002/(SICI)1521-4095(200002)12:3<202::AID-ADMA202>3.0.CO
[3]  
2-L
[4]  
Brabec CJ, 2001, ADV FUNCT MATER, V11, P15, DOI 10.1002/1616-3028(200102)11:1<15::AID-ADFM15>3.0.CO
[5]  
2-A
[6]  
Cook MJ, 1993, SPECTROSCOPY NEW MAT, P87
[7]   Crystal network formation in organic solar cells [J].
Dittmer, JJ ;
Lazzaroni, R ;
Leclère, P ;
Moretti, P ;
Granström, M ;
Petritsch, K ;
Marseglia, EA ;
Friend, RH ;
Brédas, JL ;
Rost, H ;
Holmes, AB .
SOLAR ENERGY MATERIALS AND SOLAR CELLS, 2000, 61 (01) :53-61
[8]   Bulk-heterojunction photovoltaic devices based on donor-acceptor organic small molecule blends [J].
Gebeyehu, D ;
Maennig, B ;
Drechsel, J ;
Leo, K ;
Pfeiffer, M .
SOLAR ENERGY MATERIALS AND SOLAR CELLS, 2003, 79 (01) :81-92
[9]   Dependence of field-effect hole mobility of PPV-based polymer films on the spin-casting solvent [J].
Geens, W ;
Shaheen, SE ;
Wessling, B ;
Brabec, CJ ;
Poortmans, J ;
Sariciftci, NS .
ORGANIC ELECTRONICS, 2002, 3 (3-4) :105-110
[10]   Organic co-evaporated films of a PPV-pentamer and C60:: model systems for donor/acceptor polymer blends [J].
Geens, W ;
Aernouts, T ;
Poortmans, J ;
Hadziioannou, G .
THIN SOLID FILMS, 2002, 403 :438-443