Low-temperature synthesis of lead-free Cs2AgBiBr6 double perovskite ink

Reduced toxicity and better atmospheric stability have made Cs2AgBiBr6 double perovskite material a promising photo-absorbing material to replace lead halide based perovskite in solar photovoltaic applications. In this work, for the first time, a novel low-temperature method for the synthesis of lead-free Cs2AgBiBr6 double perovskite ink, using a salt solution of the constituents of Cs2AgBiBr6 at a temperature of as low as 50°C, has been reported. X-ray diffraction study confirmed the presence of Cs2AgBiBr6 double perovskite crystal structure and a UV-visible absorption study was done to calculate the band-gap. Particle size analysis showed that the particle size, in the prepared ink, lies in the range of 700-1000  nm, while scanning electron microscopy was done on a spin-coated substrate to examine the microstructural features of the ink. The present work will help develop a low-cost and simple method for the development of the double perovskite ink further.