Elucidating interfacial charge extraction from CdTe@ZnS quantum dots by pyridinium ionic liquids
Debabrata Chakraborty1,2, Sahadev Barik1,2, Himanshu Bhatt1,2
1School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute Jatni, Khurda, Bhubaneswar 752050, Odisha, India. msarkar@niser.ac.in.
Nanoscale
|July 8, 2026
Summary
Ionic liquids (ILs) effectively accept photoinduced electrons from cadmium telluride/zinc sulfide (CdTe/ZnS) quantum dots (QDs), enhancing charge transfer. This study validates ILs as electron acceptors, crucial for advancing quantum dot solar cell technology.
Area of Science:
- Materials Science
- Photovoltaics
- Nanotechnology
Background:
- Interfacial issues like defects and energy mismatch in quantum dot (QD) solar cells limit efficiency.
- Ionic liquids (ILs) are explored for QD modification, primarily for stability, but their electron-accepting role is unestablished.
Purpose of the Study:
- Investigate photoinduced charge-transfer dynamics between CdTe@ZnS QDs and pyridinium-based ILs.
- Determine the efficacy of ILs as photoinduced electron acceptors from QDs.
Main Methods:
- Utilized steady-state and time-resolved photoluminescence spectroscopy.
- Employed Stern-Volmer analysis, zeta potential measurements, and ultrafast transient absorption spectroscopy.
Main Results:
- Observed significant photoluminescence quenching of QDs by ILs, indicating electron transfer.
- Confirmed efficient electron transfer from QDs to ILs, with dicationic IL showing highest efficiency.
- Spectroscopic data validated ILs as electron acceptors and revealed electrostatically driven QD-IL interactions.
Conclusions:
- Pyridinium-based ILs act as effective electron acceptors, modulating exciton dynamics in CdTe@ZnS QDs.
- Findings provide fundamental insights into interfacial electron transfer in QD-IL systems.
- This research guides the design of advanced optoelectronic materials integrating QDs and ILs.
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