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Abstract Polymer nanocomposite coatings of solar photovoltaic cells that absorb solar ultraviolet (UV) radiation and convert it into visible and near-infrared (NIR) light can increase the operational lifetime and the energy efficiency of the cells. We report a polymer nanocomposite spectrum converting layer (SCL) made of colorless polyimide CORIN impregnated with the nanoparticles (NPs) of fluoride NaYF₄doped with three-valent ions of Europium at a molar concentration of 60%. The NPs were the nanocrystals (179 ± 35 nm in size) in thermally stable hexagonal beta-phase. The visible-NIR photoluminescence quantum yield of the nano-powder was ∼69%. The SCLs were applied using the open-air multi-beam multi-target pulsed laser deposition method to silicon heterojunction (SHJ), copper-indium-gallium-selenide (CIGS), and inverted metamorphic multijunction (IMM) solar cells. The cells were exposed to UV radiation from a 365 nm light emitting diode. TheI–Vcharacteristics of the cells were measured with a solar simulator using AM0 filter. The proposed SCLs improved the UV stability of all three types of the cells: the power degradation of SHJs and IMMs cells was stopped or slightly reversed and the degradation rate of CIGSs decreased by ∼25%. The proposed SCLs have great commercial potential, especially for applications to space power. 

Abstract The microstructures of materials typically undergo significant changes during shock loading, causing failure when higher shock pressures are reached. However, preservation of microstructural and mechanical integrity during shock loading are essential in situations such as space travel, nuclear energy, protection systems, extreme geological events, and transportation. Here, we report ex situ shock behavior of a chemically optimized and microstructurally stable, bulk nanocrystalline copper–tantalum alloy that shows a relatively unchanged microstructure or properties when shock compressed up to 15 GPa. The absence of shock-hardening indicates that the grains and grain boundaries that make up the stabilized nanocrystalline microstructure act as stable sinks, thereby annihilating deformation-induced defects during shock loading. This study helps to advance the possibility of developing advanced structural materials for extreme applications where shock loading occurs.