Observation of Space Charge Dynamics Inside an All Oxide Based Solar Cell
ACS NANO, cilt.10, sa.6, ss.6139-6146, 2016 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 10 Sayı: 6
- Basım Tarihi: 2016
- Doi Numarası: 10.1021/acsnano.6b02090
- Dergi Adı: ACS NANO
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.6139-6146
- Anahtar Kelimeler: ZnO nanorods/Cu2O, Kelvin probe force microscopy, surface potential, charge carrier, interface, PROBE MICROSCOPY, CARRIER DYNAMICS, ELECTRON, ENERGY, SEMICONDUCTORS, RECOMBINATION, NANOCRYSTAL, COLLECTION, SEPARATION, TRANSPORT
- İstanbul Üniversitesi Adresli: Hayır
Özet
The charge transfer dynamics at interfaces are fundamental to know the mechanism of photovoltaic A 4 processes. The internal potential in solar cell devices depends on the basic processes of photovoltaic effect such as charge carrier generation, separation, transport, recombination, etc. Here we report the direct observation of the surface potential depth profile over the cross-section of the ZnO nanorods/Cu2O based solar cell for two different layer thicknesses at different wavelengths of light using Kelvin probe force microscopy. The topography and phase images across the cross-section of the solar cell are also observed, where the interfaces are well-defined on the nanoscale. The potential profiling results demonstrate that under white light illumination, the photoinduced electrons in Cu2O inject into ZnO due to the interfacial electric field, which results in the large difference in surface potential between two active layers. However, under a single wavelength illumination, the charge carrier generation, separation, and transport processes between two active layers are limited, which affect the surface potential images and corresponding potential depth profile. Because of changes in the active layer thicknesses, small variations have been observed in the charge carrier transport mechanism inside the device. These results provide the clear idea about the charge carrier distribution inside the solar cell in different conditions and show the perfect illumination condition for large carrier transport in a high performance solar cell.