Advanced hematite nanomaterials for newly emerging applications

Abstract

Recent advances in hematite nanomaterials for newly emerging applications were reviewed with a special focus on the relationship between the practical performance and electronic structure modulation.

Solid-State Reaction of Ferrocene Controlled by Co-Precursor and Reaction Atmosphere Leading to Hematite and Cohenite Nanomaterials: A Reaction Kinetic Study

“…Synthesis and characterization of iron oxide nanoparticles have become an exciting area of research as these materials possess many outstanding characteristics like low-energy band gap, high sensitivity, tunable optical and magnetic properties, superparamagnetism, biodegradability, biocompatibility, and high stability. − Among the different iron oxides known so far, magnetite (Fe 3 O 4 ), maghemite (γ-Fe 2 O 3 ), and hematite (α-Fe 2 O 3 ) are the most commonly found in nature, whereas hematite is the most stable iron oxide at ambient atmosphere, and thus, hematite nanoparticles are paving newer avenues of applications. − Though hematite nanoparticles are available in different morphologies and synthesized using different physical and chemical methods, thermal synthesis of hematite nanoparticles from iron-organic solid precursors at comparatively low temperatures has become a significantly convenient synthetic method . This technique has a number of benefits, apart from the synthesis at comparatively low temperatures, such as quick reaction time, control by reaction environment, and use of a variety of iron-organic compounds as precursors …”

Enhancement of the electrochemical oxygen reduction performance by surface oxygen vacancies on hematite nanosheets

“…Inexpensive and redox-active 3d transition metal elements such as Fe, Co, and Ni are commonly used in electrocatalysis, and hematite (a-Fe 2 O 3 ), the most stable phase among iron oxides, [16][17][18] has shown potential as an efficient electrocatalyst. 19 However, its slow adsorption of O 2 molecules and weak cleavage of OQO bonds limit its use in the oxygen reduction reaction. To enhance the ORR activity of a-Fe 2 O 3 , several strategies have been proposed, including synthesis of different nanostructures, 20,21 compositing with conductive substrates, 22,23 doping heteroatoms in the lattice, 8 and generating defects such as oxygen vacancies.…”

Synergistic Low-Pt Modification and Ni Doping Facilitate the MoS2 Phase Transition for Accelerating the Hydrogen Evolution Reaction

“…Global population expansion is happening quickly and the approaching dilemma of fossil fuel scarcity, coupled with the associated pollution issues, 1,2 has necessitated urgent efforts toward the development of new clean energy sources. 3−7 Hydrogen (H 2 ) is recognized as a clean fuel solution for energy resources because it is nonpolluting, widely available, and has high combustion energy.…”

“…Global population expansion is happening quickly and the approaching dilemma of fossil fuel scarcity, coupled with the associated pollution issues, , has necessitated urgent efforts toward the development of new clean energy sources. − Hydrogen (H 2 ) is recognized as a clean fuel solution for energy resources because it is nonpolluting, widely available, and has high combustion energy. − In recent years, electrocatalytic water splitting has attracted sustained attention among various hydrogen production technologies, primarily due to its ability to produce high-purity green hydrogen under carbon-free conditions. , However, the hydrogen evolution reaction (HER) exhibits sluggish kinetics in alkaline conditions, necessitating the use of efficient electrocatalysts to trigger proton reduction and improve reaction kinetics. Currently, the Pt metal remains the preferred high-quality electrocatalyst for the HER, emphasizing the need to maximize the available Pt in practical HER electrocatalytic processes.…”