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Hybrid gold-based perovskite derivatives typically exhibit low optical bandgaps and high optical absorption coefficients, rendering them promising for photovoltaic applications. In this study, we successfully synthesized six new hybrid gold-based perovskite derivatives, namely [(C6H8N2)(AuI4)(AuI2)](3AMPY), [(C6H14N2)(AuI4)(AuI2)](3AMP), [(C8H12N)(AuI4)](2PEAI), [(C4H14N2O)(AuI4)2](OBA), [(C6H18N2O2)3(AuI4)4(I3)2](DDA), and [(C10H26N2O3)(AuI4)(I3)](TOTA), through a straightforward and efficient hydrothermal method, achieving millimeter-sized single crystals. The structural analysis of the single crystals revealed variations in crystal structures arising from differences in constituent units and their spatial positioning relationships. First-principles calculations ascertained their high optical absorption coefficients in the visible light spectrum and indirect bandgap properties. Theoretical models indicated that the spectroscopic limited maximum efficiency (SLME) values of 3AMPY, 2PEAI, DDA, and TOTA approached approximately 30% in films of 0.5 μm thickness, signifying their potential candidacy as solar cell absorbers. [ABSTRACT FROM AUTHOR]

Although perovskite films have excellent extinction coefficients, further increase of the light‐absorbing capacity by increasing the thickness of the active layer is always required in perovskite solar cells (PSCs). However, to maintain the morphology quality of the perovskite layer, the film thickness is subject to certain restrictions. To increase the light absorbance without significantly inflating the perovskite film while keeping the high quality of the perovskite film, herein, we added an aqueous solution of gold nanorods (AuNRs) to the perovskite precursor solution via a so‐called asynchronous synergistic effect (ASE) strategy of water and AuNR. The former improves the quality of the perovskite film during the crystallization process to reduce defect density and enhance carrier mobility. Simultaneously, the latter increases the light absorption of the perovskite layer through the localized surface plasmon resonance (LSPR) effect when the device is exposed to light. We show that the ASE strategy leads to an excellent power conversion efficiency (PCE) of 21.73 % and outstanding long‐term stability, which can retain 95 % of its initial PCE after storage for three months in an air atmosphere. [ABSTRACT FROM AUTHOR]

Tandem solar cells (TSCs) comprising stacked narrow‐bandgap and wide‐bandgap subcells are regarded as the most promising approach to break the Shockley–Queisser limit of single‐junction solar cells. As the game‐changer in the photovoltaic community, organic–inorganic hybrid perovskites became the front‐runner candidate for mating with other efficient photovoltaic technologies in the tandem configuration for higher power conversion efficiency, by virtue of their tunable and complementary bandgaps, excellent photoelectric properties, and solution processability. In this review, a perspective that critically dilates the progress of perovskite material selection and device design for perovskite‐based TSCs, including perovskite/silicon, perovskite/copper indium gallium selenide, perovskite/perovskite, perovskite/CdTe, and perovskite/GaAs are presented. Besides, all‐inorganic perovskite CsPbI3 with high thermal stability is proposed as the top subcell in TSCs due to its suitable bandgap of ≈1.73 eV and rapidly increasing efficiency. To minimize the optical and electrical losses for high‐efficiency TSCs, the optimization of transparent electrodes, recombination layers, and the current‐matching principles are highlighted. Through big data analysis, wide‐bandgap perovskite solar cells with high open‐circuit voltage (Voc) are in dire need in further study. In the end, opportunities and challenges to realize the commercialization of TSCs, including long‐term stability, area upscaling, and mitigation of toxicity, are also envisioned. [ABSTRACT FROM AUTHOR]

We describe a new dynamic Monte Carlo model to simulate the operation of a polymer-blend solar cell; this model provides major improvements with respect to the one we developed earlier [J. Phys. Chem. B 114, 36 (2010)] by incorporating the Poisson equation and a charge thermoactivation mechanism. The advantage of the present approach is its capacity to deal with a nonuniform electrostatic potential that dynamically depends on the charge distribution. In this way, the unbalance in electron and hole mobilities and the space-charge induced potential distribution can be treated explicitly. Simulations reproduce well the experimental I-V curve in the dark and the open-circuit voltage under illumination of a polymer-blend solar cell. The dependence of the photovoltaic performance on the difference in electron and hole mobilities is discussed. [ABSTRACT FROM AUTHOR]

We present recent progresses on applying the theoretical models and computational tools in assessing the performance of organic solar cells, especially the bulk heterojunction solar cells. Both the continuum device model and the dynamic Monte Carlo model are developed to investigate the photocurrent-voltage characteristics based on the exciton and charge carrier dynamics. Insights into key factors influencing the organic photovoltaic performances have been gained from these studies. [ABSTRACT FROM AUTHOR]

We simulated the performance of recently developed highly efficient bulk heterojunction photovoltaic cells with poly [N-9″-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] as the donor and [6,6]-phenyl C70-butyric acid methyl ester as the acceptor, using a device model. The simulated current-voltage curve is in excellent agreement with the experiment. This enables us to analyze how microscopic processes of excitons and charges govern the device performance. The influence of dissociation rate and decay rate of photoinduced electron-hole pairs on the open-circuit voltage VOC is investigated. It is shown that a high dissociation rate relative to decay rate will lead to enhanced VOC. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have been widely studied during the past 10 years. Albeit the excellent light‐absorption ability, the thickness of the perovskite layer is limited to maintain effective control over morphology and carrier migration. Meanwhile, the quality of perovskite films is a crucial factor affecting the performance of final devices. The traditional one‐step process for preparing triple‐cation perovskite films suffers from small grain size, low crystallization quality, and many surface defects. Herein, in the process of triple‐cation perovskite‐based solar cells, a facile dosing strategy of a silver nanorods (AgNR) aqueous solution into the perovskite precursor is adopted. The localized surface plasmon resonance effect of AgNR enhances the light‐capture ability of the perovskite layer without increasing the thickness. At the same time, the presence of appropriate water helps to obtain high‐quality perovskite films with larger grain size and fewer defects. It is found that the synergy of AgNR and water successfully reduces the defect density and increases mobility significantly. Consequently, a power conversion efficiency of 20.18% and a short‐circuit current (JSC) of 22.08 mA cm−2 is achieved. Meanwhile, an excellent fill factor beyond 82% is reported, which is one of the highest values for triple‐cation hybrid PSCs. [ABSTRACT FROM AUTHOR]