| Work Detail |
An international research group has analyzed the most important barriers that prevent antimony trisulfide solar cells from achieving satisfactory power conversion efficiencies and has suggested a series of optimization parameters that could bring them closer to commercial production.
An international research team led by the Bangladesh Atomic Energy Commission has developed a new design of thin film solar cells based on antimony trisulfide (Sb2S3).
Until now, this type of cell has been far from reaching commercial production due to the low crystallinity and high resistivity of the Sb2S3 film, which affects efficiency. However, Sb2S3 has a good bandgap, ranging between 1.70 and 1.90 eV, and a notable light absorption coefficient, so it remains a promising material for future photovoltaic cell applications.
With this in mind, the researchers studied the transport mechanisms, resistance and defects of Sb2S3 cells. “The novelty of this work lies in the detailed theoretical examination of Sb2S3 solar cells, specifically focusing on the intricate interplay of various transport mechanisms, such as tunneling-enhanced recombination, recombination at the Sb2S3/CdS interface, and recombination. non-radiative”, they explained.
To address these obstacles, the research group adopted a modeling framework to analyze transport mechanisms and their interactions. “The main objective of this study is to meticulously determine the dominant recombination mechanism,” they stated, noting that other factors that influence the efficiency of an Sb2S3 cell are the doping of the cadmium sulfide (CdS) layer, the thickness, bandgap and affinity.
The scientists also investigated the effects of shunt resistance (Rsh) and series resistance (Rs) on cell performance, as well as the impact of interfacial defects at the CdS/Sb2S3 interface.
The proposed model was applied to a conventional Sb2S3 cell structure that integrated a glass-coated indium tin oxide (ITO) substrate, a CdS layer, a Sb2S3 absorber, and a gold (Au) metal contact. This analysis demonstrated that increasing the doping and thickness of CdS improves the generation and separation mechanisms by enhancing the electric field and absorption rate.
“The optimized solar cell configuration demonstrates significant improvements with a high short circuit current density of 9.5 mA cm-2, an open circuit voltage of 1.16 V, a fill factor of 54.7% and a remarkable 30% increase in conversion efficiency compared to conventional solar cells,” the scientists noted, adding that the proposed cell design can achieve an efficiency of 11.68%, which would compare with 6.5% of an unoptimized device.
“The simulation work not only sheds light on current limitations and possibilities, but also lays the foundation for future lines of research,” the team concluded.
The new cell architecture was presented in the study “ Scrutinizing transport phenomena and recombination mechanisms in thin film Sb 2 S 3 solar cells ,” published in scientific reports . The research team is made up of scientists from the HNS-RE2SD Laboratory of Algeria, the Autonomous University of Querétaro (Mexico), the Saveetha Institute of Medical and Technical Sciences of India and the Chettinad Academy of Research and Education, as well as the University King Saud of Saudi Arabia and Yeungnam University of South Korea. |
