In this work, a theoretical study on the impact of loss mechanisms on Sb2(S1−xSex)3 solar cells with a 10% certified world record efficiency is presented. In particular, it is found that CdS/Sb2(S1−xSex)3 interface recombination is the main loss mechanism, giving rise to a Voc deficit of almost 50% and a reduction in the efficiency of 45% compared to results obtained under the ideal radiative regimen. Under this mechanism, experimental observations, such as the J–V curve, efficiency, short-circuit current density, open-circuit voltage, fill factor, and external quantum efficiency, are reproduced. Finally, a discussion on the path to further promote device efficiency is presented and discussed.

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This work reports the results obtained from applying a non-linear optimization method to the I-V characteristic of a GaAlP/GaAlAs/Ge solar cell. Modifications done to the Hooke–Jeeves method are reported. Later, this method was combined with a semi-analytical approach. This provides the starting conditions for the modified Hooke-Jeeves method. Our proposal was validated by comparing its results to the ones obtained by other methods. When minimizing the difference between the experimental measurements of the I-V characteristic and a theoretical model of the solar cell, good agreements are found, and this is reflected in a reduced relative error, under 2%. In this way, the parameters forming the theoretical model are estimated.

In this work, we evaluate the role of the ternary compound, Cd1–x Zn x S, as an electron-transport layer (ETL) in the n-i-p structure of antimony selenide (Sb2Se3) solar cells. The incorporation of Zn reduces the amount of Cd and contributes to improving the power-conversion efficiency of the solar cell. On the other hand, the n-i-p structure makes it possible to overcome two issues that impair the efficiency of Sb2Se3 solar cells: the potential barrier due to the rear contact and the low hole concentration in the Sb2Se3 absorber material. In this paper, we present a theoretical work on Sb2Se3 solar cells using the SCAPS 1-D software. The theoretical analysis allows us to understand the impact of the semiconductor parameters on efficiency and also to find the optimal values for an optimized device. The optimal molar composition of the ternary compound is investigated in the superstrate and inverted configurations. Parameters such as the thickness, defect density, and the acceptor concentration of the Cd1–x Zn x S and Sb2Se3 layers are optimized. Also, we analyze the impact of interface-defect density at the hole-transport layer (HTL) (Sb2Se3) and the ETL (Sb2Se3). Following optimization, a power-conversion efficiency (η) of 14.29% is obtained using Cd0.4Zn0.6S as the ETL and Cu2O as the HTL in the superstrate configuration. This simulation process is expected to guide other experimentalists in the design and manufacture of solar cells.

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Sb2(Se1−x S x )3 compounds have been regarded as an excellent absorber in thin film solar cells processing. At present, the best efficiency reported in these chalcogenides of antimony corresponds to FTO/CdS/Sb2(Se1−x S x )3/Spiro‐OMeTAD/Au structure with 10.5%. Herein, a comparative study on the Sb2(Se1−x S x )3 solar cell performance with different electron transport layers (ETLs) and hole transport layers (HTLs) is carried out. The main photovoltaic parameters such as short‐circuit current density, open‐circuit voltage, fill factor, power conversion efficiency, and external quantum efficiency of devices with n–i–p structures are analyzed from a theoretical point of view. The impact of different ETL, HTL, and absorber thicknesses as well as the influence of Sb2(Se1−x S x )3 bulk and interface defects on the final efficiency of the device is investigated. After the optimization of the above physical parameters, it is demonstrated that with the FTO/ETL/Sb2(Se1−x S x )3/HTL/Au proposed structure, efficiency can be improved from 10% to 16%. In particular, it is found that Cd0.6Zn0.4S and ZnO are better candidates for ETL, while the use of NiO and Cu2O as HTL results in increased efficiencies in comparison to the traditional Spiro‐OMeTAD.

Molecular dynamics simulations of NO-doped Ar solid upon Rydberg photoexcitation of the impurity have been carried out taking into account angular dependent potential energy surfaces (PESs) in the ground and excited states. To go beyond isotropic potentials simulations, the effects of anisotropy of potentials on the structure, dynamics, and energetics are investigated by taking into account two cases, namely, the whole PESs and the isotropic parts. Results have been compared to those obtained in previous works for similar NO-doped rare gas systems. Radial distribution functions (RDF) for the ground and excited state indicate that for both cases the shell structure of the lattice is kept ordered and is characterized by well-defined bands. No influence of the anisotropy of potentials has been detected in the RDFs since the anisotropy is rather manifested at short distances. The well part, which has been proven to be unimportant for the dynamics in previous works, arises here to be important for the right simulation of the spectrum. In general, our results show a reasonable agreement with respect to the experimental values for the dynamics and energetics when ab initio potentials are used, although better results can be obtained if higher level ab initio PESs are used.