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In this paper, we focus on optimizing the solar performance of a CZTSSe-based solar cell by adjusting the zinc and sulfur concentrations in the CdZnS buffer layer and the quinary absorber CZTSSe. The state-of-the-art work is to combine the ZnS and CdS binaries into CdZnS ternary used as a buffer layer in both CZTS- and CZTSSe-based solar cells. An overall study of its properties is carried out taking into account the strain present at the heterointerface, defect density, bandgap energy and the interface state density. As a result, the highest efficiency η = 14.59% was achieved with a sulfur content of 0.55 and a zinc content of 0.70 to bandgap energies of 1.25 and 3.12 eV for CZTSSe and CdZnS materials, respectively. Our simulation is validated by the reproducibility of solar cell performance under the same conditions, and an enhancement of the conversion efficiency of about Δη = 5.55% will be achieved when the CdS layer is replaced by CdZnS in the ZnO/CdS/CZTSSe/Mo/Glass solar device. [ABSTRACT FROM AUTHOR]

Summary: This effort is founded on the modeling and simulation of the GaAsPN/GaP quantum dot (QD) solar cell. This quaternary alloy is one of the III‐V semiconductors, which gained importance in the recent years for optoelectronic applications. This importance comes from the fact that the quaternary GaAsPN can be a well‐grown lattice matched to GaP and Si substrates and to the bandgap that can be decreased drastically with the incorporation of nitrogen and arsenic into GaP, improving consequently the absorption and the wavelengths near the red part. These qualities make GaAsPN a good candidate for the growth on the Si substrate and low‐cost solar cell fabrication. The optical properties of GaAsPN/GaP QDs, such as strain, critical thickness, bandgap energy, the external quantum efficiency, and absorption coefficient, have been reported. The heterostructures consist of GaAs0.18P0.814N0.006 QDs separated by GaP barrier layers. The width and thickness of QDs are about 5 and 5 nm, respectively. Our results have been shown that 20 GaAs0.18P0.814N0.006/GaP QD layers produce a short‐circuit current of about 3.55 mA/cm2 and an efficiency of about 7.5%. In addition, we will be able to extend the absorption edge of a GaP solar cell from 0.48 μm to 0.5 μm for the same QD number layers inserted. The temperature effect on efficiency is considered. [ABSTRACT FROM AUTHOR]

This paper focuses on studying and simulating a GaAs1-xPx/Si1-yGey/Ge triple-junction solar cell structure. First, the strain and the bandgap energy associated to the SiGe layer have been studied. The optimal germanium concentration is 0.88 with a strain around 0.45%. Then, the phosphor concentration effect on the strain and the bandgap energy of the upper layer GaAs1-xPx/Si0.12Ge0.88 has been optimized. At room temperature, the optimal output parameter reach Jsc=34.41mA/cm², Voc=1.27V, FF=88.42% and =38.45% for an absorber thickness of 4.5µm and x=0.47, with a strain that doesn't exceed 1.5%. This study has enabled us to design a high-efficiency, low cost 3J solar cell. [ABSTRACT FROM AUTHOR]

The electrical properties of InAsP/Si quantum dot solar cell (QDSC) are numerically studied and analyzed in this paper. Many effects like number of quantum dot (QD) layers inserted and Arsenic content of InAs x P 1-x on photovoltaic properties such as current density-voltage J-V and the external quantum efficiency (EQE) are investigated. Our results have been shown that the optimal Arsenic content is 0.6. With 30 InAsP/Si QDs layers, relative enhancements of about 7% and 6.70% of short-circuit current and efficiency are achieved, respectively. Otherwise, the absorption range edge of low energy photons was extended from 1120 to 1200 nm. This reveals that introduction of QDs in the intrinsic region of p -i- n Silicon (Si) solar cell enhances significantly the device characteristics beyond what has been reported for conventional semiconductor-based solar cells. [ABSTRACT FROM AUTHOR]