Solution‐Processed Wafer‐Scale Ag ₂ S Thin Films: Synthesis and Excellent Charge Transport Properties

Monoclinic α-Ag2S is an intriguing member of transition metal sulfides with great potential for all-inorganic flexible optoelectronics and thermoelectrics. Fabrication large-area, high-quality thin films understanding their charge transport properties are critical device operations yet have remained largely unexplored. Here, a novel two-step, the solution-processed approach reported to produce wafer-sized, highly crystalline films. Ultrafast terahertz (THz) conductivity measurements reveal that photogenerated carriers undergo efficient band transport, room-temperature mobility ≈150 cm2 V-1 s-1 diffusion length exceeding 500 nm. Furthermore, introducing poly(vinyl alcohol) (PVA) as rigid component into aqueous silver thiolate precursor enables synthesis free-standing ≈35 s-1, demonstrating optoelectronics. This study provides facile route high-quality, large-area good properties, relevant integration wearable electronics.