本研究使用銅鋅錫硫四元半導體材料取代一般常用之白金對電極應用於染料敏化太陽能電池之 中，討論將該材料製備成太陽能電池元件後其元件效率，進而提出使用單面照光以及雙面照光進行元件數據分析，了解該半導體材料於此系統中所觸動之機制。並探討元件以銅鋅錫硫四元半導體材料取代後，其結構、品質與特性等對於不同電解液濃度之各種表現。
最後發現該半導體材料應用於染料敏化太陽能電池可貢獻其光觸媒光催化之特性，大幅影響其光電流，表現增幅達24.75%，接著也證明了該元件的穩定性是可靠的，因此該材料確實為可取代成本高之昂貴白金，成為良好對電極材料。

In this work, we have synthesized Cu2ZnSnS4 (CZTS) nanocrystal by solvothermal method and it is used as a counter electrode in the place the Platinum in dye-sensitized solar cells (DSSCs). CZTS is one of the promising materials to replace the platinum due to the earth abundant, low cost and non-toxic material. The synthesized CZTS nanocrystals were characterized by XRD, Raman, XPS, UV-vis spectra, FE-SEM and TEM. The obtained results were compared with reported results and listed out the advantages of our results. In addition, it’s confirmed that CZTS nanocrystals could be acted as photocatalyst in DSSCs.
In this work, we have used both single-side and double-side illumination to measure the performance of DSSC devices. The result of short-circuit current density for double-side was increased about 24.75% when compared to the single-side illumination. Also we studied the different concentration of electrolyte that contain I- and I3- to find out the photocatalytic activity of CZTS nanocrystal. Finally, we have standardized the concentration of electrolyte which can provide the highest short-circuit current density and also proved the stability of CZTS nanocrystal as counter electrode in DSSCs.

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