Fig. 4: Device and materials stability.
From: An antibonding valence band maximum enables defect-tolerant and stable GeSe photovoltaics
a Long-term stability (ambient atmosphere, room temperature, relative humidity of 50–85%), b operational stability (ambient atmosphere, continuous 1-sun illumination, close to maximum power point), c ultraviolet photostability (200–400 nm ultraviolet light irradiation), and d thermal cycling stability (cycling between −40 to 85 °C for 60 cycles) of unencapsulated GeSe devices. e Temperature-dependent XRD patterns of GeSe film from 25 to 400 °C in ambient atmosphere. XPS spectra of f Ge, Se, C, and O, g Ge 3d, and h Se 3d in the GeSe film after temperature-dependent XRD measurements.
