X pert3

The morphologies of the samples were analyzed using high-resolution scanning electron microscopy (SEM) on a ZEISS SUPRA 40VP instrument (Carl ZEISS, Germany) and field-emission transmission electron microscopy (FE-TEM) on a TALOS F200X (200 keV) instrument (FEI, Netherlands). The TEM instrument was combined with energy-dispersive X-ray spectroscopy (EDX) elemental mapping analysis. Crystal structures in the synthesized samples were studied using X-ray diffraction (XRD) on an Xpert³ (Malvern Panalytical Ltd., Netherlands) diffractometer with Cu-Kα radiation at λ = 0.15406 nm. N₂ sorption isotherms were constructed from the data acquired at −196 °C using a Micromeritics ASAP 2020 surface area analyzer (Micromeritics Instrument Corp., US). Before analysis, samples were degassed under N₂ flow at 150 °C for 12 h. X-ray photoelectron spectroscopy (XPS) was utilized to investigate the surface chemical properties using an ESCALab250-AXIS SUPRA instrument (Kratos Analytical Ltd., UK). The optical properties were studied using UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) with V-770 (JASCO Corp., Japan) and photoluminescence (PL) spectroscopy with F-7000 spectrofluorometer (Hitachi, Japan). The photodegradation of MO and RhB was monitored using acquired UV-Vis absorption spectra UV-1800 instrument (Shimadzu, Japan).

Characterization was performed on both raw and cured samples to help identify effects of carbonation. The raw powder was used as is for characterization. For the cured samples, one specimen from each batch was picked and pulverized into a fine powder. It was then characterized by TGA, XRD, and SEM. About 15 mg of powder was used for the TGA scans in a TA Instruments Q50 thermogravimetric analyzer. The samples were heated from room temperature to 1,000 °C at a rate of 20 °C min⁻¹ in an inert N₂ atmosphere. XRD characterization was performed using a Malvern Panalytical XPert³ powder diffractometer. Powdered samples were packed into a circular sample holder and exposed to Cu Kα radiation (operating conditions: 40 V and 40 mA). XRD scans were carried out for 2θ angles between 5° and 80° at a step size of 0.04° and step interval of 0.05 s per step. MDI’s JADE 6 software was used for phase identification, and Maud software was used to apply the Rietveld refinement method. Further details of phase composition calculations, based on both XRD and TGA results, are provided in SI Appendix, Section III. SEM images were obtained using a Zeiss Sigma VP Scanning Electron Microscope. Powder was scattered on carbon tape and coated with Au Pd to reduce charging.

Powder samples were prepared under argon in 0.5 mm quartz capillaries. The capillaries were filled with 2 cm of powder and were then sealed with epoxy resin. XRD measurements were realized with a PANalytical X'Pert 3 diffractometer equipped with a capillary spinner, using Cu Kα wavelength (λ = 0.15418 nm) and operating at 40 mA per 45 kV. Measurements were made within an angular range of 8–80° over 15 h.