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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. 

There is ever growing interest in sensitive detection of short wavelength (SWL) radiation, ultraviolet (UV) and X-rays. We report on our efforts to develop sensitive SWL detectors based on the nanoparticles (NPs) of lanthanide (Ln) doped Cs-Pb-bromide perovskite and oxysulfides that down-convert the spectrum of SWL radiation into visible and near-infrared (NIR) light. The spectrum of this light matches the spectral response of inexpensive and rugged silicon avalanche photo diodes (APDs) and image sensors with an electron gain of >106. Synthesized Eu-doped perovskite NPs demonstrated a down-shifted visible-NIR photoluminescence (PL) response to UV radiation with the spectral peaks attributed to both perovskite matrix and Eu dopant. A scintillating screen made of red nanophosphor Gd2O2S: Eu was used for X-ray see-through imaging of a metal object hidden in an opaque medium. Integration of the nanophosphor with a silicon APD made it possible to detect pulsating X-rays at frequencies of 20 and 40Hz with a signal-to-noise ration of ~5. The results obtained might be used in the field of sensitive detection of SWL radiation.