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A series of CsPbBrxI3-x NC glasses, showing tunable emission (523-693 nm) controlled by different ratios of Br- and I-, were successfully prepared. The CsPbBrxI3-x NC glasses exhibited excellent optical properties and outstanding stability towards ambient conditions, water and heat.

In this paper, the terahertz (THz) and infrared (IR) characteristic absorption spectra of aqueous glucose solutions and aqueous fructose solutions with different concentrations were measured and studied. The absorption spectra of these two molecules in solid-state and in aqueous solutions were compared and analyzed, the significant effect of molecular adjacent environment on the molecular structure and vibrational mode was revealed. In addition, the THz and IR absorption spectra of these two isomers’ aqueous solutions were also compared and explored. No obvious differences were found from their IR absorption features measured at room temperature, while their THz absorption spectra do have the differences, indicating THz characteristic absorption spectra more suitable for the detection and identification of aqueous glucose and fructose solutions. The results are helpful to understand the influence of aqueous solutions environment on the molecular structures and vibrational modes of the materials, and also provide a theoretical reference for the quantum chemical calculation of biological macromolecules.

2D MXene-based catalysts, such as Ti 3 C 2 T x have unique, excellent properties and show extraordinary advantages in many catalytic reactions. However, as cocatalysts for photocatalytic hydrogen evolution reaction (HER), MXene has insufficient catalytic activity because the active metal sites of H þ binding are hidden by passivation ÀF/ÀO termination, which hinders postreaction desorption of H 2 . A simple ultrasonic treatment method is used to expose more active sites and adjust the surface work function of Ti 3 C 2 T x , and additionally inactive ÀF/ÀO terminal groups are replaced with diaminoethanethiol, denoted as Ti 3 C 2 -A x , as the surface terminal group through covalent bonds (TiÀS). The optimized photocatalyst (Cd 0.4 Zn 0.6 S/Ti 3 C 2 -A 40 ) demonstrates excellent catalytic activity (HER: 13.44 mmol h À1 g À1 ), which is about 5.8 and 1.9 times higher than that of pristine Cd 0.4 Zn 0.6 S and Cd 0.4 Zn 0.6 S/Ti 3 C 2 with stability (24 h of cycle experiments), outperforming most of the reported MXene-based photocatalysts. The results of relevant experiments and density functional theory calculations reveal that the excellent conductivity of Ti 3 C 2 -A 40 , well-structured Cd 0.4 Zn 0.6 S/ Ti 3 C 2 -A 40 Schottky junction, and the efficient interfacial charge transfer are major factors that contribute to the improved photocatalytic mechanism. This promotes application of surface-modified MXene as an efficient cocatalyst and provides a new idea for design and synthesis of heterojunction materials.