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Ga2O3, as an ultra-wide band gap material with physical properties such as large atomic number, low intrinsic carrier density, and high irradiation tolerance, has shown great potential in X-ray detection. This letter reports a self-powered X-ray detector based on vertical p-NiO/Ga2O3 heterojunction diodes (HJDs). Benefiting from the high quality and high built-in potential of the p-n heterojunction, the HJD detector exhibited a pronounced photovoltaic response to X-rays at 0 V with a sensitivity of 212 nC $\cdot $ Gy $^{-1}\cdot $ cm−2 and a fast response time of less than 0.02 s in transient X-ray response measurements, which was much faster than that of the reported Ga2O3 Schottky barrier diode (SBD) detector. The power-voltage (P-V) test indicated that the device conformed to typical photovoltaic characteristics with a maximum output power of 2.95 nW. Moreover, the HJD detector showed a good linear property to various X-ray dose rates from 0.0383 Gy $\cdot \text{s}^{-1}$ to 1.149 Gy $\cdot \text{s}^{-1}$ .

A CsPbBr3single crystal exhibits great potentials in X-ray/gamma-ray spectroscopy and imaging. Here, an inverse temperature crystallization (ITC) method with modified precursor composition is proposed to prepare CsPbBr3single crystals. The introduction of adduct PbBr2·2DMSO, synthesized by the antisolvent vapor-assisted crystallization method, in the precursor solution gives rise to superior crystallization with a lower impurity concentration and higher resistivity of 6.37 × 109Ω·cm, as well as a higher hole mobility (50.7 cm2·V–1·s–1). Furthermore, a low dark current of 2.3 nA is obtained at a bias of −100 V based on an as-grown crystal with a thickness of 1 mm, according to the asymmetric Au/CsPbBr3/Sn structure. The resulting asymmetric planar detectors achieve the high peak-to-valley ratio pulse height spectra with an energy resolution of 7.66%, illuminated by an uncollimated 241Am@5.5 MeV α particle. Simultaneously, an energy resolution of 13.5% is realized when irradiated by a 59.5 keV 241Am γ-ray source at room temperature. The thermally stimulated current (TSC) spectra indicate that the density of deep energy-level trap is significantly reduced in the CsPbBr3crystals grown by PbBr2·2DMSO-modified precursor solution, which is consistent with the high performance in radiation detection.