Logo image
Back
Enhanced photovoltaic performance of dye sensitized solar cells using cesium bromide modified TiO2 electron transport layer
Journal article   Peer reviewed

Enhanced photovoltaic performance of dye sensitized solar cells using cesium bromide modified TiO2 electron transport layer

Chandan Dawo, Maimur Hossain, Parameswar Krishnan Iyer and Harsh Chaturvedi
Materials chemistry and physics, v 320, 129396
01 Jul 2024
DOI: https://doi.org/10.1016/j.matchemphys.2024.129396

Abstract

Bandgap engineering Dye sensitized solar cell Electron transport layer Improved efficiency Interfacial engineering
TiO2 is one of the most widely explored materials as an electron transport layer (ETL) in dye sensitized solar cells (DSSCs) due to its excellent physical and chemical properties. However, recombination at the device's interface slackens the charge carrier movement, adversely affecting their device performance. Rapid extraction of photogenerated charge carriers plays a vital role in developing high efficiency DSSCs. The conduction band alignment of TiO2 ETL and N719 dye light absorber plays a crucial role in charge carrier dynamics of DSSCs. Herein, the band structure of TiO2 ETL is finely tuned by the incorporation of cesium bromide (CsBr). At the optimal concentration (0.4 Wt. %), DSSCs achieved the best power conversion efficiency (PCE) of 9.28 % compared to 7.61 % for pristine TiO2. The modified TiO2–CsBr ETL induced a negative shift in flat band potential (Vfb) from −0.46 to −0.50 V, which improved the open circuit voltage (VOC), its work function (ɸ) from −4.71 to −3.75 eV and increased conduction band minimum (CBM) from −3.58 to −2.42 eV. CsBr incorporation increased electron density in TiO2 matrix, indicating the suppression of trap state and significantly improved the overall photovoltaic performance of DSSCs. •DSSC fabricated with TiO2–CsBr (0.4 Wt.%) electron transport layer achieved the best power conversion efficiency of 9.28 %.•The modified TiO2–CsBr induced a faster electron transport and shifting flat band potential (Vfb) from −0.46 to −0.50V.•After modification the work function (ɸ) of TiO2 reduced from −4.71 to −3.75eV.

Metrics

1 Record Views
3 citations in Web of Science

Details

Logo image