Seminars and Workshops Low-temperature processed natural hematite as an electron extraction layer for efficient and stable perovskite solar cells

 

Topic of Research Seminar: Low-temperature processed natural hematite as an electron extraction layer for efficient and stable perovskite solar cells

Abstract: Organic-inorganic metal halide perovskite solar cells (PSC) have emerged as a contender to market-dominating silicon counterparts owing to their low-temperature solution processing and high efficiency. In PSCs, electron extraction layer (EEL) plays a crucial role as it controls charge transport/extraction from the perovskite absorber layer to the EEL and also determine interfacial recombination and charge accumulation at the EEL/perovskite interface. In this work, a high-purity natural hematite (α-Fe2O3) is reported for the first time as the EEL in triple cation perovskite (CsFAMA) solar cells. To show the cost-effectiveness of this novel EEL, the entire device fabrication process was carried out at a temperature below 150 °C. The optimal α-Fe2O3 EEL show a mobility value of 9.5×10-4 cm-2 V-1 s-1 and trap densities of around 2.40×1016 cm-3; the latter is close to state-of-the-art SnO2 EEL (1.26×1016 cm-3). The PSCs employing optimal EEL concentration of 10 mg/ml demonstrated a power conversion efficiency (PCE) of 13.3 %, fill factor of 68 %, and VOC of 1.03 V. X-ray diffraction studies show a high crystallinity of natural hematite whereas the photoluminescence studies show a fast carrier extraction from the perovskite to the EEL. The natural α-Fe2O3-based PSCs exhibited superior shelf-life stability of over 30 days due to less charge recombination and smoother CsFAMA thin film deposited over α-Fe2O3 EEL. The low-temperature processed natural α-Fe2O3 EEL can therefore be a promising EEL material for low-cost efficient PSCs.

Subject Field of Topic: Solar Cells

Name of Speaker: Akbar Ali Qureshi

Professorial Rank of Speaker: PhD Scholar

University Email of Speaker: aali.phdscme@student.nust.edu.pk

Affiliation of Speaker: NUST School of Chemical and Materials Engineering (NUST-SCME)

Date and Venue: December 06, 2022, at 1400 hrs, Seminar Hall, School of Chemical and Materials Engineering (SCME), NUST Islamabad Campus