Exploration of Nd-Doped MAPbBr ₃ Single Crystals for Potential Space X-ray Detection

The rapid expansion of commercial spaceflight is driving space X-ray detectors toward ultimate cost-effectiveness. Compared with conventional semiconductors, metal halide perovskites, with superior optoelectronic properties and low-cost solution processability, are promising candidates for space radiation detection. Herein, we first synthesized Nd-MAPbBr 3 single crystals, with Nd 3+ causing lattice contraction and thus improving the crystal tolerance factor. We uncover a correlation between color evolution and crystallization, with the precursor solution turning purple from colorless after adding NdBr 3 and yellowing during crystallization due to methylamine oxidation. The fabricated planar Nd-MAPbBr 3 X-ray detector exhibits a sensitivity of 162.64 μC Gy –1 cm –2 and a detection limit of 4 μGy s –1 under a low electric field of 20 V cm –1 . Notably, after cumulative X-ray irradiation of 320 mGy, the sensitivity of the Nd-MAPbBr 3 detector improves by 33.75%, demonstrating superior radiation tolerance. These results highlight Nd-MAPbBr 3 single crystals as a promising material for space X-ray detection.