X‑ray-Induced Pyroelectric Effect in a Perovskite Ferroelectric Drives Low Detection Limit Self-Powered Responses

The light-induced pyroelectric effect (LPE) has shown
a great promise
in the application of optoelectronic devices, especially for self-powered
detection and imaging. However, it is quite challenging and scarce
to achieve LPE in the X-ray region. For the first time, we report
X-ray LPE in a single-phase ferroelectric of (NPA)2(EA)2Pb3Br10 (1, NPA = neopentylamine,
EA = ethylamine), adopting a two-dimensional trilayered perovskite
motif, which has a large spontaneous polarization of ∼3.7 μC/cm2. Its ferroelectricity allows for significant LPE in the wavelength
range of ordinary visible light. Strikingly, the X-ray LPE is observed
in 1, which endows remarkable self-powered X-ray responses
at 0 bias, including sensitivity up to 225 μC Gy–1 cm–2 and a low detection limit of ∼83.4
nGy s–1, being almost 66 times lower than the requirement
for medical diagnostics (∼5.5 μGy s–1). This work not only develops a new mode for X-ray detection but
also provides valuable insights for future photoelectric device application.