Sunlight-driven water splitting using hematite nanorod photoelectrodes

Abstract

The efficiency of nanostructures for photoelectrochemical water-splitting is fundamentally governed by the capability of the surface to sustain the reaction without electron trapping or recombination by photogenerated holes. This brief review will summarize the latest progress on hematite, designed with columnar morphology via chemical synthesis, for photoelectrochemical cell application. The columnar morphology efficiently minimizes the number of defects, grain boundaries, and surface traps normally present on the planar morphology. The major drawback related to hole diffusion through the solid/liquid interface was addressed by using high annealing temperature combined with dopant addition. A critical view and depth of understanding of these two parameters were discussed focusing on the molecular oxygen evolution mechanism from the sunlight-driven water oxidation reaction.

Synthesis, Characterization and Photocatalytic Activity of CoFe2O4/Fe2O3 Dispersed in Mesoporous KIT-6

“…The band gap value depends on the size and shape of particles; thus, the energy increased as the particle size of semiconductor nanomaterials decreased [ 44 ]. This may explain the different values found in the literature, especially for pure hematite, which has a typical value of 2.2 eV [ 45 ].…”

How does anodization time affect morphological and photocatalytic properties of iron oxide nanostructures?

“…In this case, nanostructures were evaluated by registering photocurrent density versus applied potential in order to evaluate their suitability as photocatalysts for water splitting. The reactions occurring in the electrochemical cell during photocurrent density versus applied potential tests were the followings [3,4,47]:…”

Influence of properties of hematite films on electrical characteristics of isotype heterojunctions Fe2O3/n-CdTe

“…Hematite (α-Fe 2 O 3 ) is the most stable iron oxide in atmospheric conditions. Its use for the photoelectrochemical water splitting system is due to the resistance to water, as well as the magnitude of the band gap E g ≈2.2 eV [8,9]. For efficient absorption and transformation of radiation energy, the electrodes for solar water splitting are made on the basis of the heterojunction Si/Fe 2 O 3 [2,5].…”