A New Electron Transport Layer for Perovskite Solar Cells

by | Jan 5, 2016

A team of Chinese scientists have developed an opal-like TiO2 electron transport layer for perovskite solar cells.

Perovskite-coated-IOT-ETL-filmA team of Chinese scientists from the School of Science and Engineering in Shanghai have developed a multifunctional inverse opal-like TiO2 electron transport layer (IOT-ETL) for a cost-efficient perovskite solar cell with high power conversion Efficiency.

Organometallic halide perovskite based solar cells have recently attracted much attention. These solar cells have excellent photovoltaic performance and are cost-efficient. In their recent publication, X.Chen, S.Yang, Y. C. Zheng, Y. Hou, X. H. Yang and H. G. Yang introduced an IOT-ETL, which was produced by a simple polystyrene-assistant method. It was created to replace the traditional compact layer and mesoporous scaffold layer in perovskite solar cells. The new devise improved the light harvesting efficiency by enhancing the light scatting property in the devices.

For further improvement the thickness of electron transport layer (ETL) films and charge recombination between electrons holes were studied. The thickness of ETL films is closely related to the power conversion efficiency (PCE) of solar cells. By changing the speed of spin-coating with the same concentration of precursor solution the thickness was optimized. The highest PCE was found at 4000 rpm.

The performance of IOT-ETL films with and without bottom based perovskite solar cells were also compared. It was found that the bottom of IOT-ETL film could prevent the direct contact between perovskite and fluorine-doped thin oxide (FTO) glass, which inhibits the light recombination of electrons and holes at the surface.

Improved light harvesting efficiency and charge transporting performance in IOT-ETL based PSCs yield high power conversion efficiency of 13.11%. This multifunctional inverse opal-like TiO2 based electron transport layer will be a promising photo-electrode for designing high-performance and low-cost perovskite solar cells. More importantly, it will pave the way for introducing photonics structure in perovskite solar cells.

Advanced Science is a new journal from the team behind Advanced MaterialsAdvanced Functional Materials, and Small. The journal is fully Open Access and is free to read now at www.advancedscience.com.