Chujie Wang

Abstract Metal halide perovskites represent a family of the most promising materials for fascinating photovoltaic and photodetector applications due to their unique optoelectronic properties and much needed simple and low‐cost fabrication process. The high atomic number ( Z ) of their constituents and significantly higher carrier mobility also make perovskite semiconductors suitable for the detection of ionizing radiation. By taking advantage of that, the direct detection of soft‐X‐ray‐induced photocurrent is demonstrated in both rigid and flexible detectors based on all‐inorganic halide perovskite quantum dots (QDs) synthesized via a solution process. Utilizing a synchrotron soft‐X‐ray beamline, high sensitivities of up to 1450 µC Gy air −1 cm −2 are achieved under an X‐ray dose rate of 0.0172 mGy air s −1 with only 0.1 V bias voltage, which is about 70‐fold more sensitive than conventional α‐Se devices. Furthermore, the perovskite film is printed homogeneously on various substrates by the inexpensive inkjet printing method to demonstrate large‐scale fabrication of arrays of multichannel detectors. These results suggest that the perovskite QDs are ideal candidates for the detection of soft X‐rays and for large‐area flat or flexible panels with tremendous application potential in multidimensional and different architectures imaging technologies.

Phase-stable perovskite CsPbI₃ nanocrystals have been prepared by replacing conventionally used oleic acid with a phosphinic acid in their synthesis.

Metal halide perovskite semiconductor nanocrystals have emerged as a lucrative class of materials for many optoelectronic applications. By leveraging the synthetic toolboxes developed from decades of research into more traditional semiconductor nanocrystals, remarkable progress has been made across these materials in terms of their structural, compositional, and optoelectronic control. Here, we review this progress in terms of their underlying formation stages, synthetic approaches, and postsynthetic treatment steps. This assessment highlights the rapidly maturing nature of the perovskite nanocrystal field, particularly with regard to their lead-based derivatives. It further demonstrates that significant challenges remain around precisely controlling their nucleation and growth processes. In going forward, a deeper understanding of the role of precursors and ligands will significantly bolster the versatility in the size, shape, composition, and functional properties of these exciting materials.

Inspections based on ionizing radiation have spread into various areas including our daily lives, industries, and scientific investigations and now face increasing demands with the development of society. Commercial X-ray detectors are mostly based on an indirect operation model in which the scintillator transforms X-ray photons into visible light and bottom photodiodes convert them into images. Obviously, the performance of the scintillator determines the final imaging properties, and the pursuit of scintillators with superior properties and lower cost is ongoing. Recently, inorganic lead halide perovskite nanocrystals (PNCs) emerged as promising scintillators for X-ray imaging. Here, we make a detailed conclusion of the superiority of PNC scintillators and take a new look at their scintillation performances. Discrepancies are discussed and some suggestions are proposed. Finally, perspectives on future developments, advice to the field, and proposed solutions to the problems toward full device performance and practical applications are provided.

A liquid bridge induced assembly strategy to align perovskite QDs in one direction for high-performance photodetectors.