Dxr2 spectrometer

X-ray diffraction (XRD) patterns were obtained at room temperature on a Bruker AXS D-8 diffractometer using Cu-Kα radiation in Bragg–Brentano geometry (θ-2θ). Fourier transform infrared (FT-IR) was performed on an ABB Bomem FTLA 2000 spectrometer equipped with a Golden Gate single reflection ATR accessory. The Raman spectra were recorded in the range from 400 to 1400 cm⁻¹ with a Thermo Scientific DXR2 spectrometer. Scanning electron microscopy images were recorded on a FEI Quanta 200 microscope after carbon metallization. Specific surface area was determined from the nitrogen adsorption/desorption isotherms (at-196 °C) and measured with a Quantachrome Autosorb-1 automatic analyzer using the BET equation.

Raman vibrational spectra were achieved on a DXR2 spectrometer (Thermo, Waltham MA, USA), which was excited by a 532 nm laser. The crystal structures of the samples were performed on an Ultima IV (XRD, Rigaku, Tokyo, Japan) with Cu Kα irradiation (λ = 0.15418 nm), and the range of diffraction angles was controlled at 5–80°. The morphology and element mapping images were taken on a Regulus 8100 (SEM, JOEL, Tokyo, Japan). The local images were taken on a 2100F (TEM, HRTEM, JOEL, Tokyo, Japan). The XPS spectra were conducted on Escalab Xi⁺ (Thermo) with Al-Kα (hν = 1486.6 eV), which were calibrated based on C1s of adventitious carbon at 284.8 eV. The diffuse reflectance UV-Vis spectra were obtained on a UV-2700 (Shimadzu, Tokyo, Japan) using BaSO₄ as background. The nitrogen adsorption and desorption isotherm and pore size distribution were measured and analyzed by Autosorb-iQ-MP-C (Quantachrome, Norcross, GA, USA). The PL spectra were conducted on a FLS 980 (Ediburgh, livingston, Scotland, UK) using a Xenon lamp with an excitation wavelength of 375 nm at room temperature (293 K). The in-situ ESR signals were collected on an EMX plus (Bruker, Berlin, Germany) under visible-light irradiation (λ ≥ 420 nm). The photoelectrochemical measurements were carried out on PARSTAT 4000A (Princeton, NJ, USA). The ICP–MS test was measured on an Agilent 730ES (Palo Alto, CA, USA).