Semiconductor sensitized solar cells

1. Semiconductor sensitized solar cells

2. DSSC 的缺點 • 染料: dye 只能吸收一部分的太陽光譜 (dye:350-750 nm, 太陽光350-2500 nm). • 電解液: I 離子具腐蝕性，液體怕漏 • 光電子會recombination，降低電池之電流及效率。

4. 染料為有機物(organic) ，遇高溫會破壞 有機物長時間穩定性較差，壽命問題 電解液為碘液體，有腐蝕性，降低壽命。

5. Semiconductor 為無機物，熔點高，長期穩定 無機物比較不怕電解液腐蝕 可用的semiconductor 選擇多，發展空間大 Semiconductor sensitizers

6. Extremely thin absorber semiconductor sensitized solar cells (極薄層半導體敏化太陽電池)

10. Semiconductor absorber materials: PbS, CdSe, CdS, In2S3, Sb2S3, Cu2-xS • electron conductor:TiO2 • hole conductor: CuSCN, PEDOT • Thickness of semiconductor absorber: ~ several nm or 10 nm. • A solid-state solar cell. • Efficiency 3-4%

11. Semiconductor Quantum-dot sensitized solar cells • What is a quantum dot: a nanoparticle of diameter several 100 to a few nm. • When diameter ~ 10-20 nm, quantum effect occurs. • Quantum dot semiconductor materials: CdS, CdSe, CdTe, PbS, PbSe, InP, InAs, etc.

12. Advantages of QD-DSCs • 吸收能帶可調整(tunable absorption bands)—quantum size effect • 高吸收係數(high extinction coefficients)—較染料高 • 多電子電洞對生成(multiple electron-hole pair generation)-一個入射光子可產生數e-h對，量子效率大於100% 。