Interfacial Defect Passivation and Photophysical Modulation in Cesium Lead Chloride Perovskite Quantum Dots Using Bisbenzimidazolium Ligands for Advanced Optoelectronic Devices

Muhammad Amir Abbas; Jamaluddin Mahar; Nasir Ali; Muhammad Junaid; Muhammad Shahid Rasool

doi:10.5281/zenodo.19666800

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Muhammad Amir Abbas Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan ##default.groups.name.author##
Jamaluddin Mahar Department of Chemistry, Quaid-E-Azam University Islamabad, Islamabad, Pakistan ##default.groups.name.author##
Nasir Ali Departments of Physics, Government Degree College Saleh Pat, Sukkur, Pakistan ##default.groups.name.author##
Muhammad Junaid Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan ##default.groups.name.author##
Muhammad Shahid Rasool Departments of Chemistry, University of Karachi, Karachi, Pakistan ##default.groups.name.author##

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https://doi.org/10.5281/zenodo.19666800

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Perovskite Nanomaterials, Bisbenzimidazolium Ligands, Surface Passivation Photo Physical Properties

##article.abstract##

Cesium lead chloride (CsPbCl₃) quantum dots (QDs) possess excellent photophysical properties, including high photoluminescence quantum yield (PLQY), narrow emission, and tunable bandgap, yet their applications are limited by environmental instability and surface defects that promote non-radiative recombination. In this work, bisbenzimidazolium salts were employed as surface ligands to passivate defect states in hot-injection synthesized CsPbCl₃ QDs. Spectroscopic studies revealed that ligand passivation enhanced PLQY, narrowed emission linewidth, extended carrier lifetimes, and improved stability under ambient conditions. Tauc analysis further indicated a slight bandgap widening, consistent with defect suppression. These results demonstrate the effectiveness of bisbenzimidazolium salts in stabilizing perovskite QDs, offering a promising route for high-performance optoelectronic applications.

https://doi.org/10.5281/zenodo.19666800

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Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan
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Department of Chemistry, Quaid-E-Azam University Islamabad, Islamabad, Pakistan
##submission.authorWithAffiliation##

Departments of Physics, Government Degree College Saleh Pat, Sukkur, Pakistan
##submission.authorWithAffiliation##

Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan
##submission.authorWithAffiliation##

Departments of Chemistry, University of Karachi, Karachi, Pakistan

##submission.citations##

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