Antimony selenide (Sb2Se3) has excellent directional optical and electronic behaviors due to its quasi‐1D nanoribbons structure. The photovoltaic performance of Sb2Se3solar cells largely depends on the orientation of the nanoribbons. It is desired to grow these Sb2Se3ribbons normal to the substrate to enhance photoexcited carrier transport. Therefore, it is necessary to develop a strategy for the vertical growth of Sb2Se3nanoribbons to achieve high‐efficiency solar cells. Since antimony sulfide (Sb2S3) and Sb2Se3are from the same space group (Pbnm) and have the same crystal structure, herein an ultrathin layer (≈20 nm) of Sb2S3has been used to assist the vertical growth of Sb2Se3nanoribbons to improve the overall efficiency of Sb2Se3solar cell. The Sb2S3thin layer deposited by the hydrothermal process helps the Sb2Se3ribbons grow normal to the substrate and increases the efficiency from 5.65% to 7.44% through the improvement of all solar cell parameters. This work is expected to open a new direction to tailor the Sb2Se3grain growth and further develop the Sb2Se3solar cell in the future.
Herein, antimony sulfoselenide (Sb2(S, Se)3) thin‐film solar cells are fabricated by a hydrothermal method followed by a post‐deposition annealing process at different temperatures and the impact of the annealing temperature on the morphological, structural, optoelectronic, and defect properties of the hydrothermally grown Sb2(S, Se)3films is investigated. It is found that a proper annealing temperature leads to high‐quality Sb2(S, Se)3films with large crystal grains, high crystallinity, preferred crystal orientation, smooth and uniform morphology, and reduced defect density. These results show that suppressing deep‐level defects is crucial to enhance solar cell performance. After optimizing the annealing process, Sb2(S, Se)3solar cells with an improved power conversion efficiency 2.04 to 8.48% are obtained.
- Award ID(s):
- 1950785
- NSF-PAR ID:
- 10398154
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Solar RRL
- Volume:
- 7
- Issue:
- 4
- ISSN:
- 2367-198X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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