• Munusamy, Gnanasekaran
• Varadharajan, Krishnakumar
• Narasimhan, Surumbarkuzhali
• Munusamy, Chitharaj
• Chandrasekaran, Boopathy

Abstract

The unique characteristics of metal–organic frameworks such as structural tunability, high surface area, low density, and tailored porosity have made this material suitable for different applications, compared to mineralized carbons. To improve the photocatalytic activity of α-Fe2O3, a shell of carbon with different concentrations on the core of α-Fe2O3 was prepared via hydrothermal method. The optical property, crystal phase, and morphology of the synthesized materials were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectrometer, scanning electron microscopy, and high-resolution transmission electron microscopy (HR-TEM). The HR-TEM shows a single-sphere core–shell structure of α-Fe2O3 at higher concentration of carbon (αFC3), which showed a maximum degradation of pollutant about 85% in 2 h and 40 min. It is reasoned that the major dominants O2·–and h+ enhance the degradation. The Fe3+ ions strongly promote the upconversion emission observed at excitation of 620 nm. Photocurrent and Mott–Schottky revealed that the αFC3 core–shell sample shows that the − 0.157 flat-band potential (Vfb) increased the carrier density in the near-surface region accelerating the redox performances. In short, the excellent visible light degradation ability of αFC3 against the methyl orange and high upconversion efficiency were observed in α-Fe2O3@carbon core–shell nanostructure.

Topics

• density
• impedance spectroscopy
• morphology
• surface
• Carbon
• phase
• scanning electron microscopy
• x-ray diffraction
• x-ray photoelectron spectroscopy
• transmission electron microscopy
• porosity
• optical property