太阳能电池中以聚苯胺为空穴传输材料制备方法检测方案

SYNTHETICMETALSSynthetic Metals 137 (2003)1511-1512www.elsevier.com/locate/synmet 1512S.X. Tan et al./Synthetic Metals 137 (2003)1511-15120379-6779/03/$ - see front matter C 2003 Elsevier Science B.V. All rights reserved.doi：10.1016/S0379-6779(02)01207-9 Polyaniline as a Hole Transport Material to Prepare Solid Solar Cells S. X. Tan， J. Zhai， M. X. Wan， L. Jiang*， D. B. Zhu Center for Molecular Science， Institute of Chemistry， CAS， Beijing 100080， China Abstract A conductive polymer， polyaniline is used as a hole transport material to fabricate solid-state dye-sensitised TiO solar cells.Morphology of TiOz film， I-V characteristics， and energy conversion efficiency under simulated solar irradiation will be discussed. 1. Introduction Since dye-sensitized nano-porous TiOphoto-electrochemical cells with high energy conversionefficiency and low cost is reportedin 1991 by Gratzel，these devices became potentially alternative tcconventional p-n junctions devices. Devices employingliquid electrolyte have been reported with an overallconversion. efficiency exceeding11(0%2.Butliquidelectrolyte raises significant technological problemsassociated with device sealing and stability. Therefore thereis considerable interest in the development of solid-stateelectrolyte for such devices. Solid electrolytes， includingamorphous organic hole conductor 2，2’，7，7'-tetrakis (N，N-di-p-methoxyphenyl-amine) 9，9'-spirobifluorene， coppersalts CuI4/CuSCNI5]and polymers6-71， are studied.Polymer materials are inexpensive and can be tailoredchemically to fit a wide range of purpose， so they arepractical interesting as hole conductor materialsPolyaniline， as a type of polymer， have excellent thermaland environmental . stability，adaptablele conductivity.reversible transition between doped and neutral states andsimple method to form hole conductor layer. So in thispaper， using polyaniline as a hole conductor material， thesolid-state dye-sensitized TiO solar cells are fabricated，and the characteristics of the cells are investigated. 2. Experimental A TiO2 paste， synthesized according to reference [8]，is coated on SnOz：F-coated glass substrate (sheet resistanceof 30 Q /) with glass rod to form TiO film. The thicknessand active area of film are ca. 4 um and 5.4 mm，respectively. The above film is sintered for 30 min at 450℃in oven. When cooling to 100~80℃， the film is immersedin a 2×10"M RuL(SCN)2 (Solaronix Co.) ethanol ( *Corresponding author： Tel ： +086-10-82621396 Fax： + 086-10-82625766 ) solution (where L=2，2bipyridyl-4，4'-dicarboxilate)overnight. Subsequentlyy，ppolyaniline(thieemolecularstructure of polyaniline is shown in fig. 1) in chloroformsolution was spin-coated onto the dye-adsorbed porousTiO films. Then a platinized counter electrode is clippedonto the top of polyaniline layer to form cell. All cells areproduced under ambient conditions. Fig. 1. The molecular structure of polyaniline utilized to fabricate solidstate dye-sensitized solar cells The morphology of TiO film is observed usingJSM-6700F Scanning Electron Microscope (SEM). Thecurrent-voltage (I-V) characteristics is measured by 250WCMH-250 solar simulator. 3. Results and discussion 3.1. Morphology ofTiO， film Fig. 2 shows SEM image ofthe morphology of TiOfilm. It can be observed that the structure of TiO2 film is aninterpenetrating network without crack.IInterconnectedTiO2 particles and micro-pores in the film are uniform withan average size of 30 nm. Fig. 2. SEM image of the TiO film 3.2.I-Vcharacteristics Fig. 3. I-V characteristics of solar cell at light intensity of different lightintensity. Fig. 4. A) Dependence of Voc and Isc on light intensity. B) ne plottedas function of light intensity. The inset shows the FF behavior. Fig. 3 shows I-V curves obtained with the dye-sensitized TiO2 solar cell under 10 mW/cm ， 25 mW/cm，72 mW/cm and 110 mW/cm’ illumination. Correspondingvalues for the short-circuit current (Isc)， open-circuit voltage (Voc)， fill factor (FF)， and overall solar-to-electricalenergy conversion efficiency (ne) obtained from Fig. 3 asa function of light intensity are shown in Fig. 4. The resultsshow that with the increase of light intensity， Voc and Iscincrease from 194mV and 2.2 uA/cm’ to 310 mV and 21uA/cm， but FF andn。decrease， respectively. It isinferred that at low light intensity， though the number ofphotoelectrons issmall， the external circuit readilyscavenges all electrons injected into TiO electrode. Withthe increase of light intensity， electron density increase inthe film， but the polymer electrolyte cannot transport allelectronsto externalcircuitdue tto its lowiionicconductivity 19-10. As a result， with increasing light intensity，Voc and Isc increase， while FF and n。 reduce. 4.Conclusion A solid-state dye-sensitized porous TiO solar cellusing polyaniline as hole conductor layer is successfullyfabricated. This device shows open-circuit voltage up to310 mV， short-circuit current up to 21 uA/cm’ undersimulated1 ssolarr rradiation((110 nmW/cm). 1Furtheroptimization of solar cell structure is expected to enhancethe efficiency. Reference ( [1] B.O'Regan a n d M. Gratzel， N ature， 3 5 3 (1991) 737-739 ) ( [2] M. K. Mazeeruddin， P. Pechy and M. Gratzel， J . A m. Chem. Soc.， 1 2 3(2001)1613-1624 ) ( [3] U. Bach， D. Lupo and M. Gratzel， N ature， 3 95 (1998) 583-585 ) ( [4] G. Kumara and K. Tennakone， C hem. M a ter.， 1 4(2002)954-955 ) ( [5] B. O'Regan and M. Gratzel， Adv. M ater.， 12 (2000) 1263-1267 ) ( [6] D. Gebeyehu， C. J . B r abec and N. S. Sariciftci， T hin Solid film，403-404(2002)271-274 ) ( [7] M. P aoli， A. .1 F. N ogueira， D. A. . b Machado a and 1 C . Longo，Electrochimica Acta， 46 (2001) 4243-4249 ) ( [8] C . J . Barbe ， and M. Gratzel， J . Am. Ceram. Soc. ， 80 (1997) 3 1 57-3 1 71 ) ( [9] A. F. Nogueira， J . R . Durrant and M.-A. De Paoli， Adv. M ater.， 1 3(2001)826-830 ) ( [10] A. F. Nogueira， M. - A. D e Paoli， I . M ontanari， R. Monkhoouse， J. N elson and J . R. Durrant， J. Phys. Chem.，105 (2001)7517-7524 )