Centrifugally spun hematite Fe2O3 hollow fibers: Efficient photocatalyst for H2 generation and CO2 reduction

Abstract

Mesoporous hollow hematite Fe2O3 fibers were successfully synthesized through centrifugal spinning and applied in photocatalytic H2 production and CO2 reduction. Fabrication of hollow hematite fibers includes two innovative synthetic steps: i) centrifugal spinning of precursor fibers using polyvinylpyrrolidone (PVP) as a polymeric part and two different Fe precursors (iron nitrate and iron chloride), ii) annealing of these fibers using different temperatures profiles (250 degrees C and 600 degrees C) with optimized heating rates and durations. The prepared samples (FN250, FN600, FC250, and FC600) were thoroughly characterized using SEM, XRD, XPS, and Raman spectroscopy, and the obtained results were correlated with the photocatalytic performance during H2 production and CO2 reduction. The FC250 and FC600 samples, which showed a higher concentration of oxygen defects, exhibited superior photocatalytic efficiency compared to the Fe2O3 standard. The enhanced performance is attributed to the increased light absorption, improved charge separation, and surface reactivity due to oxygenrelated defects. These results highlight the potential of non-stoichiometric Fe2O3 nanofibers for environmental remediation and energy conversion applications.