Guanidinium cation doped (Gua)x(MA)1−xPbI3 single crystal for high performance X-ray detector

Recently, halide hybrid perovskites have emerged as an attractive material for radiation detection due to their high atomic numbers and resistivity, large μ $\mathrm{\mu }$ τ $\tau$ product ( μ $\mathrm{\mu }$ is the carrier mobility ; τ $\tau$ is the carrier lifetime). However, the sensitivity and stability of perovskite X-ray detectors were limited by ion migration in the perovskites. In this paper, the guanidinium ionic (Gua + ${}^{+}$ ) doped MAPbI 3 single crystals were successfully obtained with the solution-processed method. (Gua) 0.06 ${}_{\mathrm{0.06}}$ (MA) 0.94 ${}_{\mathrm{0.94}}$ PbI 3 single crystal shows an activation energy of 589 meV. The X-ray detector with Au/(Gua) 0.06 ${}_{\mathrm{0.06}}$ (MA) 0.94 ${}_{\mathrm{0.94}}$ PbI 3 /Ga structural exhibited a high X-ray sensitivity of 2903 μ $\mathrm{\mu }$ C Gy air − 1 ${}_{\mathrm{air}}^{-1}$ cm −2 and a low limit of detection of 7.2 nGy air ${}_{\mathrm{air}}$ s − 1 ${}^{-1}$ . This work shows that a certain amount of Gua + ${}^{+}$ doping into MAPbI 3 ${}_3$ could inhibit the ion migration, and significantly improve the X-ray detection performance.