本實驗以液相法於單一反應系統中(one-pot system)利用Cu2GeSe3 (CGSe)奈米晶為模板，在270℃反應18-36小時，並以不同Zn濃度為參數合成(Cu2Ge)x/3Zn1-xSe (0.75≦x<1)奈米晶。隨著Zn前驅物濃度及反應時間的增加，由Raman光譜儀分析，CGSe模板依序轉換成(1)CGSe與CGSe-ZnSe固溶體，(2)CGSe、CGSe-ZnSe與Cu2ZnGeSe4(CZGSe)，(3)CZGSe。由穿透式電子顯微鏡分析(Cu2Ge)x/3Zn1-xSe奈米晶，其Zn濃度由外往內逐漸降低的CGSe/(CGSe-ZnSe)/CZGSe之單晶核殼(core-shell)結構，而其CGSe、CGSe-ZnSe與CZGSe的相對量取決於Zn的濃度與反應時間。本實驗(Cu2Ge)x/3Zn1-xSe奈米晶的能隙調控範圍達1.09-1.46 eV，此值涵蓋可見光及近紅外光的區域，顯示此(Cu2Ge)x/3Zn1-xSe奈米晶在太陽能電池之應用上是有益的。

(Cu2Ge)x/3Zn1-xSe (0.75≦x<1) nanocrystals were synthesized at 270°C for 18-36 h as a function of the Zn concentration in a one-pot system via the solution-phase route by using the Cu2GeSe3 (CGSe) nanocrystals as the templates. With increasing the concentration of Zn precursor and growth time the CGSe templates sequentially transformed to (1)CGSe and CGSe-ZnSe solid solution, (2)CGSe, CGSe-ZnSe, and Cu2ZnGeSe4 (CZGSe), and (3)CZGSe from Raman spectroscopy analyses. From transmission electron microscopy analyses for (Cu2Ge)x/3Zn1-xSe nanocrystals, a core-shell structure of CGSe/(CGSe-ZnSe)/CZGSe with an inward decrease in the Zn concentration was observed in the single crystal, where the relative amount of CGSe, CGSe-ZnSe, and CZGSe depended on the Zn concentration and growth time. In the present study, the band gap of (Cu2Ge)x/3Zn1-xSe nanocrystals can be tuned in the range of 1.09-1.46 eV, which are over the visible and near-infrared region, showing that they may be beneficial for photovoltaic applications.

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