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Halide perovskite (HP) nanocrystals (NCs) have recently shown great potential for X-ray detection and imaging. However, the practical application is still a long way to go with lots of technical requirements waiting to be fulfilled, including structure optimization, stability enhancement, and cost reduction. A design principle in this beginning stage is urgently needed but still lacking. Herein, with an "emitter-in-matrix" principle refined from commercial scintillators, CsPbBr3@Cs4PbBr6 with emissive CsPbBr3 NCs embedded inside solid-state Cs4PbBr6 host is brought to X-ray sensing and imaging. The Cs4PbBr6 matrix not only enhances the attenuation of X-rays but also dramatically improves the stability of CsPbBr3 NCs. A favorable optical design with the Cs4PbBr6 matrix being transparent to the emission from CsPbBr3 NCs enables efficient light output. As a result, stable and sensitive scintillation response to X-ray signals is demonstrated with superior linearity and ultrahigh time resolution.In order to show the huge potential for practical application, X-ray imaging using a large-area film (360 mm×240 mm) by blade-coating technique is carried out to obtain a high-quality image of human eye-invisible interior structures. In addition to the above advantages in optics, CsPbBr3@Cs4PbBr6 also enjoys facile solution synthesis with large scalability, excellent repeatability and low cost.

The aerosol‐assisted (AA) CVD method involves the atomization of a precursor solution into fine, sub‐micrometer‐sized aerosol droplets which are delivered to a heated reaction zone and undergo evaporation, decomposition, and homogeneous and/or heterogeneous chemical reactions to form the desired products. As a variant of conventional CVD processes, AACVD addresses the availability and delivery problems of the chemical precursors. A wide range of precursors can be used since volatility is no longer crucial, offering more possibilities to produce high‐quality CVD products at low cost. Some variants of AACVD have also been developed, such as AA combustion (C) CVD, electrostatic spray‐assisted vapor deposition (ESAVD), and electrostatic‐assisted aerosol jet deposition (EAAJD). These variants provide additional flexibility and capability to the AACVD‐based processes. AACVD‐based processes have attracted increasing interest in most of the CVD‐related areas, and have been widely used to synthesize various films, coatings, powders, composites, nanotubes and nanowires, etc. This review highlights the principles, applications, and recent progress of AACVD‐based processes.

Preferred orientation of ZnO thin films deposited by the atomic layer deposition (ALD) technique could be manipulated by deposition temperature. In this work, diethyl zinc (DEZn) and deionized water (H(2)O) were used as a zinc source and oxygen source, respectively. The results demonstrated that (10.0) dominant ZnO thin films were grown in the temperature range of 155-220 °C. The c-axis crystal growth of these films was greatly suppressed. Adhesion of anions (such as fragments of an ethyl group) on the (00.2) polar surface of the ZnO thin film was believed to be responsible for this suppression. In contrast, (00.2) dominant ZnO thin films were obtained between 220 and 300 °C. The preferred orientations of (10.0) and (00.2) of the ZnO thin films were examined by XRD texture analysis. The texture analysis results agreed well with the alignments of ZnO nanowires (NWs) which were grown from these ZnO thin films. In this case, the nanosized crystals of ZnO thin films acted as seeds for the growth of ZnO nanowires (NWs) by chemical vapor deposition (CVD) process. The highly (00.2) textured ZnO thin films deposited at high temperatures, such as 280 °C, contained polycrystals with the c axis perpendicular to the substrate surface and provided a good template for the growth of vertically aligned ZnO NWs.

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