Sta 409 pc luxx

The atomic absorption spectrometer (AAS) was applied to determine the concentration of zinc in the sample. HNO₃ acid was used for zinc dissolving and diluted to 100× dilution, and Perkin Elmer AAnalyst 400 flame was used for analysis. The phase transformation of zinc ferrite was determined using X-ray diffraction (Rigaku SmartLab 9 kW XRD). The measurements were taken using CoKα radiation operated at 40 kV voltage and a 135 mA (5.4 kW) rotating anode. A scanning electron microscope (FESEM), connected with an EDS (Energy-Dispersive X-ray Spectroscopy) analyzer (Zeiss ULTRA plus FESEM), was used to investigate the micromorphology and microanalyses of the samples.
Thermogravimetry (TG) – differential scanning calorimetry (DSC) were carried out using a Netzsch STA 409 PC Luxx. The tests were performed in an air and nitrogen atmosphere conditions from 20 to 1300 °C and a heating rate of 10 °C min⁻¹. Around 30.84 mg of the material was placed in a platinum crucible.

The obtained nanostructures were examined by transmission electron microscopy (TEM) using a JEOL JEM-2100 (JEOL GmbH, Eching, Germany). The size distributions of Au nanoparticles were determined from TEM images using the ImageJ software [39 (link)]. More than 100 Au nanoparticles were counted. For the measurement of UV–Vis absorption spectra, the reaction solution with Au@PDA particles as catalyst was placed in a quartz sample cell with a 1.0-cm cell path length. UV–Vis spectra (at 400 nm) were recorded by using Lambda 650 spectrometer supplied by PerkinElmer at 20 °C with reference spectrum of the Au@PDA particles in water. TGA measurements were taken using a Netzsch STA409PC LUXX from 25 to 600 °C under a constant argon flow (30 mL min⁻¹) with a heating rate of 10 K/min. Nitrogen adsorption experiments were performed with a Quantachrome Autosorb-1 at liquid nitrogen temperature, and data analysis was performed by Quantachrome software. The specific surface area was calculated using the Brunauer–Emmett–Teller (BET) equation. Pore size distribution was determined by Barrett–Joyner–Halenda (BJH) method. Samples were degassed at 50 °C for 24 h before measurements.

The structures of OMPW were obtained by scanning electron microscopy (SEM, JEOL 6300F, JEOL, Tokyo, Japan). The porous structure and elemental analyses of OMPW and sulfer/OMPW (S/OMPW) was characterized by transmission electron microscopy (TEM, JEOL JEM-2100F, JEOL, Tokyo, Japan). The Fourier transform infrared (FTIR) spectrum was recorded with a Bruker Tensor 27 Spectrometer (Bruker, Ettlingen, Germany). X-ray diffractometer (XRD) patterns were carried out on a Rigaku D/Max-2400 (Rigaku, Tokyo, Japan). Thermogravimetric analysis (TGA, STA 409 PC Luxx, Netzsch, Selb, Germany) was performed under Ar atmosphere to determine the S content of the S/OMPW composite. Nitrogen (77 K) adsorption-desorption isotherms were conducted using a Micromeritics Tristar II 3020 analyzer (Micromeritics, Norcross, GA, USA). X-ray photoelectron spectroscopy (XPS) investigation was carried out by using a PHI model 5700 spectrometer (Physical Electronics, Chanhassen, MN, USA).