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It is difficult to investigate the hydrogen-bonding dynamics of hydrogen-disordered ice VI. Here, we present a comparative method based on our previous study of its counterpart hydrogen-ordered phase, ice XV. The primitive cell of ice XV is a 10 molecule unit, and the vibrational normal modes were analyzed individually. We constructed an 80 molecule supercell of ice VI to mimic the periodic unit and performed first-principles density functional theory calculations. As the two vibrational spectra show almost identical features, we compared the molecular translation vibrations. Inspired by the phonon analysis of ice XV, we found that the vibrational modes in the translation band of ice VI are classifiable into three groups. The lowest-strength vibration modes represent vibrations between two sublattices that lack hydrogen bonding. The highest-strength vibration modes represent the vibration of four hydrogen bonds of one molecule. The middle-strength vibration modes mainly represent the molecular vibrations of only two hydrogen bonds. Although there are many overlapping stronger and middle modes, there are only two main peaks in the inelastic neutron scattering (INS) spectra. This work explains the origin of the two main peaks in the far-infrared region of ice VI and illustrates how to analyze a hydrogen-disordered ice structure.

In order to further develop efficient ultraviolet light-driven photocatalysts for environmental application, α-zirconium phosphate (α-ZrP) and carbon nitride (C3N4) were synthesized, respectively. Then, C3N4–ZrP compositing nanomaterials were prepared by compositing α-ZrP nanocrystals and C3N4 with different mass ratios. C3N4–ZrP compositing nanomaterials were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results illustrated that α-ZrP and C3N4 were successfully composited, and the polarization of the compositing nanomaterials was reduced compared with raw materials. The photocatalytic performances of C3N4–ZrP compositing nanomaterials with different mass ratios were studied by photodegradation of RhB under ultraviolet irradiation. All of the degradation rates of the C3N4–ZrP compositing nanomaterials system were achieved more than 90% after 18 min. When the mass ratio of C3N4–ZrP compositing nanomaterials is 2:1, the degradation efficiency achieved 99.95%, which is more efficient than other tested mass ratios. The result indicated the possibility of utilizing C3N4–ZrP compositing nanomaterials for environmental pollutants degradation.

Highly crystalline α-zirconium phosphate (α-ZrP) nanoparticles were synthesized and exfoliated into nanosheets, and then the hydrophilic nanosheets were modified into hydrophobic nanosheets with octadecyltrichlorosilane (OTS). Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis were applied to confirm the morphology and chemical structure of the nanosheets. Contact angle measurement was conducted to explore the wettability alteration of the hydrophobically modified α-ZrP nanosheets, and the result showed that the wettability of the core was changed into hydrophobicity. When ZrP-OTS nanosheets were injected during water-flooding, a Pickering emulsion will be formed. The droplet diameters and viscosities of the Pickering emulsions were measured. The hydrophobically modified α-ZrP nanosheets were applied in low-permeability sandstone cores and various concentrations were tested. The injectivity of the hydrophobically modified α-ZrP nanosheets was also studied and the result indicated that the nanosheets exhibit good injectivity. The mechanisms for enhancing oil recovery by utilizing hydrophobic α-ZrP nanosheets were analyzed: forming Pickering emulsions and increasing the viscosity of the displacing phase. Forming emulsions and increasing the viscosity of the flooding phase can enhance the microdisplacement efficiency, while good injectivity can also enhance the macrodisplacement efficiency. The result indicated the possibility of using hydrophobically modified α-ZrP nanosheets for enhancing oil recovery in a low-permeability reservoir.