TY - JOUR
T1 - Spiro[fluorene-9,9′-xanthene]-based hole shuttle materials for effective defect passivation in perovskite solar cells
AU - Yadagiri, Bommaramoni
AU - Sandhu, Sanjay
AU - Kaliamurthy, Ashok Kumar
AU - Asiam, Francis Kwaku
AU - Park, Jongdeok
AU - Mensah, Appiagyei Ewusi
AU - Lee, Jae Joon
N1 - Publisher Copyright:
© 2024 The Royal Society of Chemistry.
PY - 2023/11/21
Y1 - 2023/11/21
N2 - The molecular engineering of the interface modulator between the perovskite and hole transporting material (HTM) is crucial to achieving satisfactory performance and stability of perovskite solar cells (PSCs). Here, cruciform-shaped dual functional organic materials, denoted as SPX-TPA and SPX-BT, are employed for surface passivation and hole transporting interfacial layers (HTILs) in MAPbI3-based PSCs. The rigid three-dimensional conjugated spiro(fluorene-9,9′-xanthene) (SPX) core is identical to spiro-fluorene (existing in spiro-OMeTAD) except differentiated by one oxygen atom. This core unit can effectively adjust the HOMO level and inhibits intramolecular π-π stacking to extract holes from the adjacent perovskite layer. The small energy gap between SPX-TPA (50 meV) and the perovskite can effectively minimize voltage losses and promotes the hole shuttling process. The hydroxyl (-OH) group in the SPX unit forms hydrogen bonds with undercoordinated iodide (I−) and methyl ammonium (MA+) ions, suppressing the related defects. Lewis bases (O, N and S) in TPA and BT units can promote the passivation of undercoordinated Pb2+ and MA+ (Lewis acid) via Lewis acid-base interactions (Pb-S/O/N). As a result, the PSCs with SPX-TPA and SPX-BT exhibit significantly improved PCEs of 20.03% and 18.51%, respectively, while the PCE of the control device is 17.77%. The enhanced PV performance of SPX-TPA treated PSCs is ascribed to the well-aligned energy levels, superior hole mobility, and favorable film morphology.
AB - The molecular engineering of the interface modulator between the perovskite and hole transporting material (HTM) is crucial to achieving satisfactory performance and stability of perovskite solar cells (PSCs). Here, cruciform-shaped dual functional organic materials, denoted as SPX-TPA and SPX-BT, are employed for surface passivation and hole transporting interfacial layers (HTILs) in MAPbI3-based PSCs. The rigid three-dimensional conjugated spiro(fluorene-9,9′-xanthene) (SPX) core is identical to spiro-fluorene (existing in spiro-OMeTAD) except differentiated by one oxygen atom. This core unit can effectively adjust the HOMO level and inhibits intramolecular π-π stacking to extract holes from the adjacent perovskite layer. The small energy gap between SPX-TPA (50 meV) and the perovskite can effectively minimize voltage losses and promotes the hole shuttling process. The hydroxyl (-OH) group in the SPX unit forms hydrogen bonds with undercoordinated iodide (I−) and methyl ammonium (MA+) ions, suppressing the related defects. Lewis bases (O, N and S) in TPA and BT units can promote the passivation of undercoordinated Pb2+ and MA+ (Lewis acid) via Lewis acid-base interactions (Pb-S/O/N). As a result, the PSCs with SPX-TPA and SPX-BT exhibit significantly improved PCEs of 20.03% and 18.51%, respectively, while the PCE of the control device is 17.77%. The enhanced PV performance of SPX-TPA treated PSCs is ascribed to the well-aligned energy levels, superior hole mobility, and favorable film morphology.
UR - http://www.scopus.com/inward/record.url?scp=85180340868&partnerID=8YFLogxK
U2 - 10.1039/d3ta05915d
DO - 10.1039/d3ta05915d
M3 - Article
AN - SCOPUS:85180340868
SN - 2050-7488
VL - 12
SP - 1284
EP - 1291
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 2
ER -
