Vertex 70 fourier transform infrared spectrometer

The samples of SRP were placed in a drying oven (at 105 °C for over 2 h) to remove the free water to prevent hydroxyl groups in water molecules from affecting the sample spectrum, and the solid SRPs were then mixed with potassium bromide and pressed as mixed powder into a transparent disk by tablet press. FTIR spectra of samples were conducted on VERTEX 70 Fourier transform infrared spectrometer (Bruker Co., Rheinstette, Germany). The measurement range of wavenumber was from 500 to 4000 cm⁻¹.

In situ IR spectra of both compounds under water vapor were measured on a Bruker Vertex 70 Fourier Transform Infrared Spectrometer. Each powder sample was placed at the center of an IR cell and treated in vacuo at 423 K for 6 h. Then, the powder sample was exposed to water vapor at room temperature with equilibrium pressures of 0.5–2.50 kPa. The equilibrium of the sorption was confirmed by the fact that the spectrum did not change over time. The spectra were deconvoluted with the Gaussian function.

Steady-state luminescence spectra were acquired under excitation at 300 nm on a Hitachi F4600 luminescence spectrometer (Hitachi, Tokyo Japan). The UV-Vis absorbance spectra were recorded with a UV-3900H spectrometer (Hitachi, Japan). Thermal gravimetric analysis (TGA) was carried out using a 200F3 thermal gravimetric analyzer (Netzsch, Gebrüder Germany) at a heating rate of 10 °C/min under air condition. Transmission electron microscope (JEM-2100F) and field emission scanning electron microscopy (FE-SEM, S-4800, Hitachi, Japan) was used to characterize morphology of samples. Contact angles of the films with deionized water drop were measured with a contact angle goniometer (G-1, Erma) at room temperature. Infrared spectra of the ZnS QDs was recorded on a VERTEX 70 Fourier transform infrared spectrometer (Bruker, Karlsruhe Germany).

The phase analysis of residues was carried out using a Model ULTIMA IV X-ray diffractometer (Rigaku, Japan). It was carried out with an automated X-ray diffractometer using Cu Kα radiation (λ = 1.5418 Å), a 40 kV voltage, a 40 mA electrical current, and 2θ from 5° to 85°.
The Fourier transform infrared spectra of all samples were obtained using a Vertex 70 Fourier transform infrared spectrometer (FTIR, Bruker, Germany) by the KBr tableting method in the wavelength range of 4000–400 cm⁻¹ with a resolution of 4 cm⁻¹.
The element at the near surface of the material and its chemical state were determined by X-ray photoelectron spectroscopy (XPS, Thermo ESCALAB 250XI).
The surface morphologies of the samples were characterized with SEM (S4800).
Ultraviolet visible (UV-Vis) diffuse reflectance spectra (DRS) of the samples were measured with a UV-Vis spectrophotometer (U-3900).
The surface area and pore structure of the samples were measured by nitrogen adsorption–desorption testing on a specific surface and pore size analysis instrument (3H–2000PS2). The nitrogen sorption isotherms were measured at 77 K with a 3H–2000PS2 analyzer after the samples were degassed in a vacuum at 190 °C for 10 h.
The elements such as C, H, N, and S in the prepared samples were quantitatively analyzed by the German Elementar analyzer (EA).

Room-temperature
infrared spectra
(50–4000 cm^–1, 4 cm^–1 resolution,
64 scans, 8 × zero filling) were recorded with a Bruker Vertex
70 Fourier transform infrared spectrometer using a Bruker Platinum
single reflection attenuated total internal reflection accessory.
Some spectra were also measured in transmission as polyethylene discs
(∼1 wt % in low density polyethylene). The low wavenumber limit
(∼50 cm^–1) is determined by the very low
output of the globar infrared source at these energies, resulting
in almost no signal.

The measurement data are extracted by using Bruker VERTEX 70 Fourier-transform infrared spectrometer equipped with Bruker HYPERION 2000 infrared microscope (15× Cassegrain objective with a numerical aperture of N.A. = 0.4, near-infrared polarizer, and MCT detector). The internal iris of HYPERION microscope is used to collect the incident light to a square area of about 150 × 150 μm². The reference of reflectance spectrum is gold mirror.