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With the accelerated development of new lead-free metal halide perovskites, whose chemical and physical properties are very different from their so-studied classical Pb-containing counterparts, finding suitable synthetic methodologies for these emerging materials seems to be the new challenge. Cs4CuSb2Cl12 is a vacancy-ordered layered double perovskite promising for a large variety of optoelectronic applications. Here, the synthesis in situ of Cs4CuSb2Cl12 and Cs4CuSb2Cl12:F− films by aerosol-assisted chemical vapor deposition (AACVD) is reported for the first time. A double source AACVD was used, and the precursor salts were separated in two different precursor solutions that were simultaneously deposited, avoiding its crystallization before film formation. The methodology was then used to fabricate photoconductor devices that showed morphological, photoresponse, memory window tunability, electronic plasticity, and conductivity features that can be tuned by F− doping, demonstrating the versatility of the AACVD method for the deposition of emergent perovskite structures as films for device integration. [ABSTRACT FROM AUTHOR]

Most solution‐based synthetic routes for perovskite film deposition take place under highly controlled atmospheres and cannot be easily escalated for mass production. Here, the control in situ over luminescent, morphological, and structural characteristics of hybrid and inorganic perovskite films deposited on top of hot glass substrates by multisource AACVD is reported. By simply adjusting the methylammonium chloride (MACl) to lead bromide (PbBr2) molar ratio in the N‐N dimethylformamide (DMF) precursor solution, a gradual transformation from orthorhombic PbBr2 to cubic MAPbBr2Cl hybrid perovskite films is observed, and the generation of highly luminescent MAPbBr3−xClx nanoparticulate domains in a PbBr2 matrix is easily achieved when a specific ratio is used. Additionally, the crystallization of the films is performed in situ modified by the implementation of an antisolvent stream source during deposition which in turn yields films with superior luminescence properties. Finally, an NIR emitting CsPbBr2Cl:Yb inorganic perovskite film is deposited to probe the versatility of the multisource AACVD system, by the simultaneous deposition of separated PbBr2/YbCl3·6H2O/DMF and CsCl/methanol solutions. The high degree of control on the final properties of the films indicates that AACVD could be a breakthrough for low‐cost, scalable, high‐throughput metal‐halide perovskite film deposition. [ABSTRACT FROM AUTHOR]

ZrO2 and ZrO2:Sm3+ nanopowders are synthesized by means of polyol method, from [Zr(NO3)2.xH2O] and (SmCl3·6H2O) precursors dissolved in a diethylene glycol medium. X‐ray diffraction (XRD) results show polymorphic powders because monoclinic structure and tetragonal are exhibited. The crystal size is estimated by Scherrer formula; an averaged crystallite size of 9 nm is obtained. Surface morphology study, by means of SEM, evidences multiform particles, some with straight edges associated with monoclinic or tetragonal structure. The chemical composition microanalysis results indicate agreement with ideal stoichiometry for ZrO2 and ZrO2:Sm3+ powders. The photoluminescence emission spectra show that maximum intensity is reached at λ = 614 nm due to transition 4G5/2→6H7/2, exciting with λex = 240 nm, which corresponds to sample ZrO2:Sm3+ (0.75 at%); this sample is labeled as M3. Very similar results are obtained by cathodoluminescence studies. On the contrary, exciting with λex = 380 nm (monitoring emission band peaked at 614 nm), emission bands of host lattice and ZrO2:Sm3+ are favored simultaneously. The luminescent quenching phenomenon occurs when doping concentration (Sm3+ ions) is >=0.75 at%. The photoluminescent emission exhibits a reddish orange color, characteristic of Sm3+ ions, and yellowish‐orange for cathodoluminescence emission. [ABSTRACT FROM AUTHOR]