Lithium Incorporation into Sol-Gel-Processed Chalcogenide Photovoltaic Absorbers: A Simple and Efficient Strategy
Naoufal ENNOUHI, Nisar ALI, Rosemary CHITI, Otman ABIDA, Bakhtiar ULHAQ
Abstract. Lithium doping is one of the most successful approaches used recently to improve the properties of kesterite materials and the performance of their solar cells. However, doping in sol-gel-derived kesterite is still limited to dopant incorporation during solution preparation. Here, we present a simple strategy to incorporate lithium into kesterite absorbers by depositing thin Li-containing layer onto kesterite precursors via the spin-coating method. Compared with conventional doping approach, this method led to enhanced film quality. Comprehensive structural and morphological analysis was performed via X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). Our results confirmed a significant improvement in crystallinity, a reduction in Cu/Zn disorder, and the growth of larger and well-defined grains. Optical characterization confirmed the improved bandgap and a reduction in the defect density following lithium incorporation via the proposed strategy. The findings reported in this work demonstrate that doping via surface deposition represents a promising approach for enhancing the properties of kesterite thin films prepared using sol-gel method and can be a promising approach for developing highly efficient kesterite-based solar cells if carefully controlled.
Keywords
Kesterite, ACZTS, Lithium Doping, Sol-Gel, Thin Films, Photovoltaics
Published online 4/25/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Naoufal ENNOUHI, Nisar ALI, Rosemary CHITI, Otman ABIDA, Bakhtiar ULHAQ, Lithium Incorporation into Sol-Gel-Processed Chalcogenide Photovoltaic Absorbers: A Simple and Efficient Strategy, Materials Research Proceedings, Vol. 64, pp 664-671, 2026
DOI: https://doi.org/10.21741/9781644904091-83
The article was published as article 83 of the book Energy Futures
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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