Publications by authors named "Chanwoo Lim"
Article Synopsis
- Colloidal PbS quantum dot solar cells (QDSCs) typically use a ZnO electron transport layer (ETL), but this leads to performance issues due to energy barriers at the ZnO/PbS junction and defects in the material.
- The study introduces Sn-doped ZnO (ZTO) as an alternative ETL, successfully shifting the conduction band properties to improve electron extraction, resulting in better photovoltaic performance (open-circuit voltage of 0.7 V, fill factor over 70%, and efficiency of 11.3%).
- Analysis using X-ray photoelectron spectroscopy (XPS) showed reduced oxygen vacancies in ZTO ETL, indicating that Sn doping enhances electron extraction in PbS QDSCs
Article Synopsis
- The charge generation process in organic bulk heterojunction (BHJ) devices is still not fully understood despite decades of research, primarily due to the difficulty in measuring the polarizability of individual component materials in blends.* -
- Using spectrally resolved electroabsorption spectroscopy, researchers were able to extract the excited state polarizability of individual donor and acceptor molecules, revealing that a larger exciton polarizability correlates with greater efficiency in charge generation.* -
- The study also found that the molecular packing between donor and acceptor materials can enhance exciton polarizability, contributing to improved charge transfer across the heterojunction in BHJ photodiodes.*
Colloidal PbS quantum-dot solar cells (QDSCs) have long suffered from inefficient charge collection near the back-junction due to the lack of p-doping strategy, rendering their bifacial photovoltaic applications unsuccessful. Here, we report highly efficient photocarrier collection in bifacial colloidal PbS QDSCs by exploiting spray-coated silver nanowires (AgNWs) top electrodes. During our spray-coating process, pressurized Ag diffusion occurred toward the active layer, which induced effective p-doping and deep-level passivation.
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