Fabrication of 2D perovskite (PMA)2PbI4 crystal and Cu ion implantation improved x-ray detector

Two-dimensional (2D) perovskites have been demonstrated great promise in x-ray detection application because of their stability, tunability, and the unique electronic properties. The centimeter-sized 2D perovskite (PMA)(2)PbI4 single crystal and the corresponding x-ray detector were fabricated. The Cu ion implanted device exhibits an excellent sensitivity of 283 mu C Gy(air)(-1 )cm(-2), the significantly enhanced mobility-lifetime (mu tau) product of 8.05 x 10(-3) cm(2) V-1, and the lowest detectable dose rate of 2.13 mu Gy(air) s(-1). Experimental observation combined with the DFT calculations shows that the improvement in Cu ion implanted x-ray detection is ascribed to the enhanced photoinduced charge carrier density and mu tau product, and the increased carrier dissociation capability associated deeply with the decreased binding energy of exciton in the inorganic layer quasi-quantum well. The incorporation of the Cu interstitials by high-energy Cu ion implantation is able to introduce the donor and acceptor states with additional charge transfer channeling, resulting in the decreased exciton binding energy and fast dissociation of the exciton and the quick carrier extraction. Cu ion implantation regulating the dissociation of charge carriers in low-dimensional perovskites will motivate the application for 2D perovskite in high-performance x-ray detectors.

Automated summary

In this study, large-sized two-dimensional perovskite crystals and corresponding x-ray detectors were successfully fabricated. Copper ion implantation significantly improved the sensitivity, mobility-lifetime product, and detectable dose rate of the detectors. Experimental observations and DFT calculations showed that the enhancement in x-ray detection was due to the increased photoinduced charge carrier density and mobility-lifetime product, as well as the decreased exciton binding energy and enhanced carrier dissociation capability caused by copper ion implantation.