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Hybrid lead halide perovskites have emerged as high-performing semiconductors for optoelectronic applications such as photovoltaics. However, their toxicity and stability issues represent significant challenges. Recently, double perovskites have been suggested as an alternative and, especially, Cs2AgBiX6 (X = Cl, Br) has proved to be a promising material as it is non-toxic and highly stable. However, the low solubility of precursors has so far hampered the fabrication of high quality films. Here, we demonstrate for the first time the fabrication of Cs2AgBiBr6 films and incorporate them into working devices. Powder X-ray diffraction measurements revealed that high annealing temperatures of at least 250 °C are required to fully convert the precursors into Cs2AgBiBr6. After the optimization of the synthesis conditions, photovoltaic devices comprising our Cs2AgBiBr6 films show power conversion efficiencies (PCE …