本研究主要以金屬輔助化學蝕刻製成之無機的N型矽奈米線加上有機的P型導電高分子PEDOT:PSS所製成之混合型太陽能電池。透過銀電極取代傳統ITO作為電池陽極後，在矽奈米線長度為400 nm下探討旋塗條件對於元件表現的影響。從掃描式電子顯微鏡(SEM)的橫截面圖得知，8000 rpm對於PEDOT:PSS/SiNWs接面的改善，並可在二次旋塗獲得更進一步的增益。在二次旋塗條件可得到最佳的電池表現光電轉換效率達8.56%；開路電壓0.51V；電流密度30.52 mA/cm2。本研究所採用矽奈米線之目的是將入射光侷限在元件結構裡，以增加光吸收並提升照光電流密度。但在奈米線長度增加的同時會在表面產生更多的缺陷，這些缺陷將使的照光產生的載子容易再結合，使得電池性能下降。本研究得到300 nm長度下為最佳長度的矽奈米線，光電轉換效率達10.06%；開路電壓0.526V；電流密度32.79 mA/cm2。最後更進一步對300 nm矽奈米線進行硝酸氧化，在P-N接面之間長一層極薄的氧化層，消除矽奈米線上的缺陷並且增加PEDOT:PSS包覆矽奈米的面積，改善異質接面並提升電池的開路電壓及電流密度。在16.25%硝酸氧化60秒下得到本研究之最大光電轉換效率12.41%；開路電壓0.546V；電流密度36.36 mA/cm2；填充因子達62.5%。

Interface improvement of hybrid solar cells (HSCs) by using the cheap method via nitric acid solution to grow thin silicon dioxide between the silicon nanowires (SiNWs) and PEDOT:PSS was performed. The power conversion efficiency (PCE) of HSCs without applying surface treatment was 10.06%, open voltage (Voc) of 0.526V, current density of 32.79 mA/cm2. After exploiting surface treatment by immersing 300 nm Si nanowires (SiNWs) into 16.25% of HNO3 solutions, the tremendous enhancement on the performance of SiNWs/PEDOT:PSS based HSCs with PCE of 12.41%, Voc of 0.546V, current density of 36.36 mA/cm2, fill factor of 62.5% was demonstrated. These results reveal that the silicon dioxide would eliminate the defects and dangling bonds appearing in SiNWs and decrease the interface recombination to create the well-established p-n junction. In addition, the results elucidate that this facile interfacial treatment could enhance the open voltage remarkably as well as reach the superior PCE.

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