(PEDOT-PSS)-碳纳米管复合膜硅基太阳能电池

碳纳米管-Si(CNTs-Si)肖特基太阳能电池具有制作简单、成本低的优势。然而,受限于CNTs薄膜的电阻高、结区均匀性差、反光严重等因素,该类器件的光电转换效率仍较低。本文研究了聚3,4-乙撑二氧噻吩-聚苯乙烯磺酸盐(PEDOT-PSS)-CNTs复合透明膜的制备及其在硅太阳能电池中的应用。电流-电压曲线表明,PEDOT-PSS的引入可以大幅度提升CNTs-Si器件的光电转换效率(从5.9%到11.6%)。作为透明电极,复合膜中的取向CNTs可有效地收集和传导太阳能电池结区的光生空穴,而PEDOT-PSS则有效填补了CNTs膜的面内空隙,进而增加了肖特基结的面积。采用表面刻有倒金字塔结构的聚二甲基硅氧烷(PDMS)作为减反层,有效地降低入射光的反射,增加Si表面对光的吸收,进一步将(PEDOT-PSS)-CNTs-Si器件的光电转换效率提升至12.4%。电子束感生电流技术表明器件的光电转换主要基于复合膜与Si之间的肖特基结。

(PEDOT-PSS)-carbon nanotubes composite films for Si solar cells

Carbon nanotubes-Si(CNTs-Si)Schottky solar cells have the advantages of low cost and facile fabrica-tion.However,the applications of such devices have been limited by the low photovoltaic conversion efficiency, which is possibly derived from the high resistance of CNTs,non-uniform junction and serious light reflection.A composite film of poly(3,4-rethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT-PSS)-CNTs was prepared as a transparent conducting film for Si-based solar cell.The current-voltage curves show that the use of PEDOT-PSS considerably improves the conversion efficiencies from 5.9% for pristine CNTs-Si solar cells up to 11.6%.Aligned CNTs in the composite film facilitate the transfer of photo-generated holes in the junction region.The applied PEDOT-PSS conducting polymer fills the voids between nanotubes,improving the contact between CNTs and Si and forming additional Schottky junctions.A transparent polydimethylsiloxane (PDMS)film with an inverted pyramid structure was attached on the (PEDOT-PSS)-CNTs-Si solar cells,further improving the conversion efficiency to 12.4% by reducing light reflection loss.The electron beam induced current technique shows that the photo-conver-sion mechanism of such devices is based on a Schottky junction.