Presentation Information
[15a-PA3-11]Highly Efficient and Stable Hybrid Perovskite Solar Cells through Cu-Doped Mesoporous TiO2
〇Jiyoon Kim1, Sumin Shin1, Taewoong Kim1 (1.Konkuk Univ.)
Keywords:
Perovskite solar cell,Photodeposition
Perovskite solar cells (PSCs) have emerged as promising next-generation photovoltaic devices due to their remarkable achievements in the photovoltaic field. Over the past decade, PSCs have demonstrated unprecedented progress in power conversion efficiency (PCE), now approaching the performance of conventional silicon-based solar cells.
Titanium dioxide (TiO2)-based electron transport layers (ETLs) are widely used in PSCs but suffer from low electron mobility, deep-level defects, and detrimental interfacial recombination, which ultimately limit PCE. Mesoporous TiO2 (m-TiO2) partially alleviates these issues by providing a large surface area and improved interfacial contact, yet its intrinsic material limitations are not fully resolved.
In this study, Cu-doped mesoporous TiO2 (Cu-m-TiO2) was developed via a photodeposition approach to retain the structural advantages of m-TiO2 while overcoming the inherent drawbacks of TiO2. The Cu-m-TiO2 ETL enables simultaneous modulation of the electronic structure, surface chemistry, and energy-level alignment at the ETL/perovskite interface. The incorporation of Cu effectively regulates defect states and induces a spontaneous electronic gradient, thereby facilitating electron transport and extraction. Consequently, PSCs incorporating Cu-m-TiO2 demonstrated a VOC of 1.162 V, JSC of 26.19 mA/cm2, and FF of 84.4%, achieving a champion PCE of 25.68%, which is significantly higher than that of m-TiO2-based devices (23.12%). Beyond efficiency enhancement, Cu-m-TiO2 substantially improved device longevity, retaining 94.6% of its initial efficiency after 2,450 h under unencapsulated dry-room conditions.
This approach provides a viable ETL design strategy for realizing highly efficient and stable PSCs.
Titanium dioxide (TiO2)-based electron transport layers (ETLs) are widely used in PSCs but suffer from low electron mobility, deep-level defects, and detrimental interfacial recombination, which ultimately limit PCE. Mesoporous TiO2 (m-TiO2) partially alleviates these issues by providing a large surface area and improved interfacial contact, yet its intrinsic material limitations are not fully resolved.
In this study, Cu-doped mesoporous TiO2 (Cu-m-TiO2) was developed via a photodeposition approach to retain the structural advantages of m-TiO2 while overcoming the inherent drawbacks of TiO2. The Cu-m-TiO2 ETL enables simultaneous modulation of the electronic structure, surface chemistry, and energy-level alignment at the ETL/perovskite interface. The incorporation of Cu effectively regulates defect states and induces a spontaneous electronic gradient, thereby facilitating electron transport and extraction. Consequently, PSCs incorporating Cu-m-TiO2 demonstrated a VOC of 1.162 V, JSC of 26.19 mA/cm2, and FF of 84.4%, achieving a champion PCE of 25.68%, which is significantly higher than that of m-TiO2-based devices (23.12%). Beyond efficiency enhancement, Cu-m-TiO2 substantially improved device longevity, retaining 94.6% of its initial efficiency after 2,450 h under unencapsulated dry-room conditions.
This approach provides a viable ETL design strategy for realizing highly efficient and stable PSCs.