Hematite and Magnetite Nanostructures for Green and Sustainable Energy Harnessing and Environmental Pollution Control: A Review

Abstract

The optoelectrical and magnetic characteristics of naturally existing iron-based nanostructures, especially hematite and magnetite nanoparticles (H-NPs and M-NPs), gained significant research interest in various applications, recently. The main purpose of this Review is to provide an overview of the utilization of H-NPs and M-NPs in various environmental remediation. Iron-based NPs are extensively explored to generate green energy from environmental friendly processes such as water splitting and CO2 conversion to hydrogen and low molecular weight hydrocarbons, respectively. The latter part of the Review provided a critical overview to use H-NPs and M-NPs for the detection and decontamination of inorganic and organic contaminants to counter the environmental pollution and toxicity challenge, which could ensure environmental sustainability and hygiene. Some of the future perspectives are comprehensively presented in the final portion of the script, optimiztically, and it is supported by some relevant literature surveys to predict the possible routes of H-NPs and M-NPs modifications that could enable researchers to use these NPs in more advanced environmental applications. The literature collection and discussion on the critical assessment of reserving the environmental sustainability challenges provided in this Review will be useful not only for experienced researchers but also for novices in the field.

A High‐Performance Asymmetric Supercapacitor Based on Tungsten Oxide Nanoplates and Highly Reduced Graphene Oxide Electrodes

“…In addition, the use of fossil fuels has a negative impact on the environment due to CO 2 emission that contributes to global warming [1–3] . The environmental problems have stimulated the interest in exploring new energy horizons [4, 5] . Renewable resources like solar and wind energy are considered the most suitable and reliable supplies of alternative energy [6, 7] .…”

Synergies of co-doping in ultra-thin hematite photoanodes for solar water oxidation: In and Ti as representative case

“…[6][7][8][9] Among the various metal oxides, iron oxide (hematite; a-Fe 2 O 3 ) 10 is considered as one of the potential photoanode candidates for solar water oxidation, thanks to its unique properties such as a suitable bandgap (2.0-2.2 eV), low cost, non-toxicity and high stability. 4,[11][12][13] However, pristine a-Fe 2 O 3 exhibits poor water splitting efficiency, far below the maximum theoretical efficiency of 12.9%, because of the mismatch between the valence band energy level and the water reduction potential, the short hole diffusion length of 2-4 nm and the low electron mobility. 8 Several strategies have been adopted to overcome the intrinsic limitations of hematite: 14 for instance, tuning the electrode morphology, 15 introduce synergistic interfaces in two-dimensional stacks of semiconductors, 16,17 surface activation with co-catalysts, 18 and doping with various metal cations to change the electronic structure.…”

Effect of preparation method in the properties of iron oxide catalysts for fenton reaction

“…The Fe-PHA sample adsorption values are consistent with the specific surface area values. Likewise, the sample prepared by combustion presents more magnetite phase than the others, thus it is more active for the oxidation test (ASHRAF et al, 2020).…”