2D Hybrid Perovskite Ferroelectric Enables Highly Sensitive X‐Ray Detection with Low Driving Voltage

Abstract

X-ray detectors with high sensitivity are of great significance in both civil and military fields. Over the past decades, great efforts have been made to improve the sensitivity in conventional inorganic materials, but mainly at the cost of increasing the energy consumption with a quite high operating voltage. Developing photosensitive ferroelectrics directly as detector materials may be a conceptually new strategy in view of the strong ferroelectric spontaneous polarization (P s ) that assists photoinduced carriers separation and transport. = 5 µC cm −2 ) is fabricated and exhibits an ultrahigh X-ray sensitivity up to 6.8 × 10 3 µC Gy air −1 cm −2 even at a relatively low operating voltage, which is over 300-fold larger than that of state-of-the-art α-Se X-ray detectors. Such a brilliant figure-of-merit is largely attributed to the superior mobility-lifetime products associated with the strong ferroelectric polarization of BA 2 EA 2 Pb 3 Br 10 . As pioneering work, these findings inform the exploration of hybrid halide perovskite ferroelectrics toward highperformance photoelectronic devices.

Unveiling the Structural Descriptor of A3B2X9 Perovskite Derivatives toward X‐Ray Detectors with Low Detection Limit and High Stability

“…[ 1–3 ] Recently, metal halide perovskites and their derivatives have achieved great successes as direct X‐ray detectors. [ 4–8 ] The heavy atoms (Pb, Bi), good carrier transport and long carrier lifetime of the materials together contribute to the excellent detection performance. [ 4–6 ] Huang and co‐workers reported that MAPbBr 3 ‐based X‐ray detectors demonstrate high sensitivity of 21000 μC Gy air −1 cm −2 and low detection limit of 38 nGy air s −1 .…”

“…[ 6 ] Besides, some newly derived ferroelectric perovskite and metal‐organic frameworks also exhibited good potential for X‐ray applications. [ 7,8 ]…”

Three-Dimensional Lead Iodide Perovskitoid Hybrids with High X-ray Photoresponse

“…Alternative materials based on double perovskites [12][13][14][15] and low-dimensional perovskites [15][16][17][18][19][20] are also being explored as they enrich the structural diversity and property repertoire of the perovskite framework. The 3D perovskite structure which forms by the corner-sharing motif of the MX 6 octahedra of Pb 2+ and Sn 2+ creates a favorable electronic band structure with very broad valence and conduction bands which facilitate photo-excited charge transport.…”

Halide Perovskite, a Potential Scintillator for X‐Ray Detection

“…[ 33–39 ] Especially, they have high atomic number ( Z ) and high‐quality elements, such as Pb, Br, and I atoms. [ 40–45 ] Because the cross‐section of halide perovskite increases with the increase of ≈ Z 4 , which makes it to naturally have good ionizing radiation absorption ability. In addition, halide perovskites exhibit inherent high carrier mobility, long carrier lifetime, high stopping power, low detection limit, and polychromatic radioluminescence (RL), which make them possess the capability for radiation detection.…”