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A AgBr–Ag2MoO4 heterojunction with high inactivation of E. coli under visible-light illumination was constructed. The crystal structure, morphology, elemental composition, and optical properties were characterized by TEM, SEM, XRD, XPS and DRS. The photocatalytic inactivation of E. coli by AgBr, Ag2MoO4, and AgBr–Ag2MoO4 was investigated. The results indicate that AgBr–Ag2MoO4 shows the best disinfection activity compared to AgBr and Ag2MoO4, with the E. coli being almost completely inactivated after illumination for 80 min. In addition, the cell structure of the bacteria is destroyed after visible-light irradiation in the presence of the catalyst. The UV absorption detection confirms that the bacterial protein leak and the concentration of nucleic acid in the solution also increase with the increase of the reaction time, indicating that the integrity of the bacterial cell membrane is damaged. The detection of ROS scavengers indicates that the reactive species (h+, ˙OH, e− and ˙O2−) play an important role in the inactivation of bacteria. The EPR tests confirm that the amount of ˙OH is higher than that of ˙O2− during the illumination process, which is consistent with the results of the free-radical capture tests. The heterojunction of AgBr–Ag2MoO4 is beneficial for the separation of photogenerated electrons and holes during the illumination process, resulting in an improvement of the antibacterial properties. [ABSTRACT FROM AUTHOR]

Mustard gas is a kind of erosive poison with great harm and used as a chemical weapon since World War. It has suggested that the photocatalytic technology is an effective method to eliminate it. Because the small difference in molecular structure between 2-CEES and Mustard gas, and the less toxic of 2-CEES, 2-CEES is often used as a simulator to evaluate the photocatalytic activity of catalysts. In this work, symbiotic mixture of Bi2WO6 and Bi6O6(OH)3(NO3)3·1.5H2O nanosheets doped with Mo (Mo-B-B) have been synthesized by a facile hydrothermal treatment. The samples were characterized by XRD, DRS, XPS, SEM, TEM, Raman, and PL. The photocatalytic activity of the samples was evaluated by measuring the degradation of 2-CEES under visible light irradiation. The results showed that the doped Mo reduce the Eg of bare symbiotic mixture and improve the separation efficiency of photo-generated carriers that is beneficial to photocatalytic activity. The optimum amount of doped Mo is 5% that exhibits the best activity for degradation for 2-CEES. [ABSTRACT FROM AUTHOR]

Self-trapped excitons (STEs) emission from halide perovskites with strong exciton-phonon coupling has attracted considerable attention due to the widespread application in optoelectronic devices. Nevertheless, the in-depth understanding of the relationship between exciton-phonon coupling and luminescence intensity remains incomplete. Herein, a doping-enhanced exciton-phonon coupling effect is observed in Cs3Cu2I5 nanocrystals (NCs), which leads to a remarkable increasement of their STEs emission efficiency. Mechanism study shows that the hetero-valent substitution of Cu+ with alkaline-earth metal ions (AE2+) causes a greater degree of Jahn–Teller distortion between the ground state and excited state structures of [Cu2I5]3− clusters as evidenced by our spectral analysis and first-principles calculations. As a consequence, an X-ray detector based on these Cs3Cu2I5:AE NCs delivers an X-ray imaging resolution of up to 10 lp·mm−1 and a low detection limit of 0.37 µGyair·s−1, disclosing the potential of doping-enhanced exciton-phonon coupling effect in improving STEs-emission and practical application for X-ray imaging. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) materials hold great promise as next‐generation efficient emitters due to their theoretical 100% internal quantum efficiency. However, such an intriguing photophysical mechanism is extremely rare in perovskites or their derivatives. Herein, the colloidal synthesis of two‐dimensional CsAgCl2 nanocrystals (NCs) with typical TADF feature is reported first. The TADF mechanism is investigated in detail by combining first‐principles calculations with experimental results, including temperature‐dependent spectral analysis and fs‐transient absorption spectra. A small singlet−triplet state splitting energy (0.082 eV) and a large spatial separation of charge density |Ψ|2 of valence band maximum and conduction band minimum are observed, which are prerequisites for TADF. Moreover, these CsAgCl2 NCs deliver an ultralow X‐ray detection limit of 170.5 nGyair s−1 and a high imaging resolution of 11.5 lp mm−1, much superior to the commercial scintillators. [ABSTRACT FROM AUTHOR]