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In this work, we have synthesized and fabricated solar cells with the hybrid metal halide compounds with the general formula ABX3, where the A cation is methylammonium, the B cation is nickel, and the X anion is chlorine or a mixture of chlorine and iodine. We obtained experimental evidence that this material is a semiconductor with an orthorhombic crystalline structure which pertains to the space group Cmcm. The bandgap can be modulated from 1.4 eV to 1.0 eV by changing the chlorine anion to iodine. Therefore, we were able to obtain solar cells with efficiencies up to 0.16% with the CH3NH3NiCl2I composition. We have also studied by means of first-principles calculations, taking into account van der Waals dispersive forces, the ground state properties of these materials such as their crystal structure and formation and decomposition energies. We have found that these energies are lowered by the lighter mass anion, and the calculated decomposition energies show that only CH3NH3NiCl3 is stable with respect to the most probable decomposition pathway. The electronic band structure and band edge alignments have been calculated using quasiparticle effects through the GW0 approximation; these materials show an indirect bandgap with the valence band maxima at −6.93 and −5.49 eV with respect to vacuum and the conduction band minima at −5.62 and −4.60 eV with respect to vacuum for CH3NH3NiCl3 and CH3NH3NiI3, respectively. This work provides a pathway to explore new hybrid A + B 2 + X 3 − -type semiconductor materials. [ABSTRACT FROM AUTHOR]

With the aim to identify the status, trends and differences from the electrical performance perspective of commercial available photovoltaic technologies, 1016 modules from different manufacturers and six leading solar technologies (m-Si, p-Si, a-Si, CIGS, CIS and CdTe) have been analyzed. The area of these devices and electrical information as power, short-circuit current, open-voltage circuit, maximum power point, efficiency and fill factor at standard test conditions were considered. With these variables, two-cluster analysis were performed with the aim of finding groups with similarities between the modules independently on the technology. Cluster results suggested that most part of modules could be divided in two main groups, one related to silicon (mono and poly), and other related to thin-film technology (a-Si, CIGS, CIS and CdTe). Because amorphous silicon presented a broad range of voltage and power, then different groups were needed to classify this technology. This cluster analysis can be used as a robust classification tool to identify patterns from the electrical point of view, allowing comparing other emerging solar technologies with respect to the most consolidated. [ABSTRACT FROM AUTHOR]

Abstract Perovskite solar cells have shown an impressive performance evolution during the last years. This technology has been mostly tested under laboratory conditions using small area devices. In this work, the outdoor photovoltaic performance of perovskite solar cells was evaluated under real tropical weather conditions. Specifically, two perovskite modules with active area of 17 and 50 cm2 were fabricated, encapsulated and tested. Taking a commercial silicon panel as reference, both technologies were evaluated for 500 h correlating the in-situ I-V measurements with atmospheric variables measured every minute during the light hours. To obtain the performance and the average outdoor efficiency of devices, we proposed a new adapted methodology based on the standard IEC 61853-1, showing the photovoltaic parameters performance through maps, to graphically visualize their behavior in a broad range of atmospheric conditions. Additionally, we demonstrated that the power delivery and short circuit current of both technologies correlate linearly with the atmospheric variables. Moreover, the open circuit voltage of perovskite technology exhibited a nonlinear behavior and an improved performance with temperature at high irradiance regimes. This work presents reliable information concerning perovskite solar technology performance under real outdoor operation conditions, being this crucial to identify competitive advantages of this technology and the aspects to be improved. Graphical abstract fx1 Highlights • Continuous perovskite solar cells monitoring under outdoor conditions. • New adapted methodology to evaluate perovskite modules. • Stable perovskite modules up to 500 h under real operation conditions. [ABSTRACT FROM AUTHOR]