Direct & efficient detection of x-ray radiation using thermally evaporated 2D hybrid lead halide perovskite (BA2PbBr4)(BA=n-Butylammonium=C4H9NH3) film

Abstract This report demonstrates fast response and direct detection of x-ray radiation by thermally evaporated 2D hybrid halide perovskite (BA 2 PbBr 4 )(n-BA=Butylammonium=C 4 H 9 NH 3 ) based film. A highly efficient pin-hole free/compact film (thickness∼1 μ m), via a controlled evaporation process, has been grown to fabricate solid-state x-ray radiation detector film (typical dimension ∼1 × 1 cm 2 ) of 2D hybrid halide perovskite BA 2 PbBr 4 ( BAPB) material. Direct detection of x-rays is possible using this detector by simple electrical readout method, where a change in resistance occurs while exposed to x-ray radiation at ambient temperature. The detector current increases when an x-ray impinges on it and exhibits the highest sensitivity ∼1000 μ C/Gy/cm 2 . The detector film shows fast response, exhibiting quick response-recovery time ∼ ms towards x-ray. The detector film exhibits reasonably high dark resistivity ∼ 10 10 Ω − cm and good mobility-lifetime ( μ τ ) product 3.308 × 10 − 6 c m 2 / s . The 2D hybrid halide perovskite (BA 2 PbBr 4 ) based detector can sustain an effective high electric field ∼5000 V cm −1 corresponding to 40 V operational bias. It shows very good radiation resistant towards x-ray and retains its crystal structure, as confirmed from structural data under sustained x-ray exposure. The 2D halide perovskite detector (BAPB) shows long-term stability or shelf life (∼4 months) and response is highly repeatable with less than 5 % fluctuation, which is an important key performance metric for any radiation detector. This detector has good application potential in several areas like, medical imaging, security checking, etc.