In a current article revealed within the journal Crystals, researchers explored the potential of versatile natural/silicon (natural/Si) tandem photo voltaic cells (TSCs) as a sustainable and environment friendly various to traditional photo voltaic vitality applied sciences. They used expertise computer-aided design (TCAD) simulations to analyze the design and optimization of those new TSCs. Their purpose is to beat the restrictions of single-junction photo voltaic gadgets and obtain increased energy conversion efficiencies (PCEs).
Background
Solar vitality is a crucial renewable useful resource able to assembly the world’s vitality wants sustainably. However, single-junction photo voltaic gadgets face a theoretical effectivity barrier often called the Shockley-Queisser restrict. To overcome this, TSCs have emerged as a promising answer. TSCs enhance photo voltaic vitality conversion effectivity by stacking a number of photoactive supplies with complementary bandgaps, enabling a wider absorption spectrum in comparison with single-junction cells.
Due to their helpful properties, natural supplies and silicon (Si) are wonderful for tandem cells. Organic supplies supply flexibility and adjustable bandgaps, whereas Si gives extremely environment friendly and well-established manufacturing processes. Flexible natural photo voltaic cells (OSCs) and thin-film Si photo voltaic cells are necessary for the event of environment friendly and versatile photovoltaic gadgets. It is good for functions that require light-weight and adaptable energy sources, similar to shopper electronics.
About Research
In this paper, the authors investigated a versatile two-terminal (2-T) natural/Si TSC, the place the OSC is the entrance cell and the Si cell is the again cell. These supplies have been chosen attributable to their non-toxicity, complementary bandgap properties, and price effectiveness. The OSC, with a bandgap of 1.78 eV, absorbs increased vitality photons, whereas the Si cell, with a bandgap of 1.12 eV, absorbs decrease vitality photons effectively. The examine aimed to guage the efficiency of this tandem configuration and determine optimization methods to enhance its effectiveness.
The researchers carried out the simulations utilizing the Atlas system simulator from Silvaco TCAD. Atlas fashions the habits of photo voltaic cells by fixing elementary semiconductor transport equations, together with service continuity and Poisson’s equations. The simulations mix numerous bodily fashions and materials parameters for natural and Si cells, together with recombination fashions similar to Shockley-Read-Hall (SRH) and Auger fashions.
Research Findings
The simulation outcomes present that the entrance OSC and rear Si cell obtain a PCE of 11.11% and 22.69%, respectively. These outcomes set up a baseline for evaluating TSC’s joint efficiency.
The authors additional investigated the efficiency of 2-T natural/Si TSC, which initially achieved a PCE of 20.03%. To enhance the effectivity, they investigated a number of optimization strategies. First, they eliminated the natural gap transport layer (HTL) and adjusted the entrance contact work operate, which elevated the PCE to 23.27%. They additionally diminished the defect density within the natural absorber layer, which additional elevated the PCE to 23.27%.
Finally, the thickness of the highest and again layers of the absorber is optimized. It reveals that the mixture of a 250 nm thick entrance natural layer and a 70 μm thick n-type Si layer achieves the best PCE of 27.60%. This optimized tandem cell configuration resulted in an improved PCE of 27.60%, an open-circuit voltage (VOC) of 1.81 V, and a short-circuit present density (JSC) of 19.28 mA/cm², which marks a big enchancment over the preliminary 20.03 % PCE of the unoptimized tandem cell.
Applications
The simulated outcomes spotlight the numerous potential of the natural/Si TSC design for numerous implications, particularly in wearable electronics and versatile photo voltaic panels. The expertise’s flexibility, environmental friendliness, and excessive effectivity make it very engaging for brand spanking new functions.
The versatile nature of the TSC permits it to seamlessly combine into wearable digital gadgets that demand an adaptable and light-weight energy supply. Its excessive effectivity and light-weight weight make it a really perfect candidate for moveable solar energy techniques. The use of non-toxic and considerable natural/Si TSC supplies helps the event of sustainable and eco-friendly photovoltaic panels.
Conclusion
In abstract, the simulations present the potential for versatile natural/Si TSCs as a promising various to traditional photo voltaic vitality applied sciences. Through efficient optimization, the tandem cell design achieves outstanding enhancements in PCE. This achievement provides priceless insights for future natural/Si tandem cell improvement, paving the best way for sensible functions in lots of fields.
The examine highlights the potential impression of mixing Si expertise with low-cost printed natural photovoltaic applied sciences, bettering industrial and social functions throughout the renewable vitality sector.
Source:
Salem, MS; Okil, M.; Shaker, A.; Abouelatta, M.; Salah, MM; Al-Dhlan, KA; Gad, M. TCAD-Based Design and Optimization of Flexible Organic/Si Tandem Solar Cells. Crystals 2024, 14584. DOI: 10.3390/cryst14070584, https://www.mdpi.com/2073-4352/14/7/584