Construction of an efficient hole migration pathway on hematite for efficient photoelectrochemical water oxidation

Abstract

In this study, we constructed an efficient hole migration pathway by integrating ultrathin amorphous NiOOH onto the Fe2O3 coating on F doped α-Fe2O3 nanorods. The resulting photoanode presents higher charge separation efficiency than most reported hematite-based photoanode.

Surface Iron Species in Palladium–Iron Intermetallic Nanocrystals that Promote and Stabilize CO2 Methanation

“…[23][24][25][26] As shown in the O1sX PS spectra of fct-PdFe nanocrystals after the treatment with CO 2 ,t he peak at 531.2 eV and 529.7 eV appeared, corresponding to the CO* and dissociated O* species,r espectively ( Figure 3b). [27][28][29] These two peaks were also observed for fcc-PdFenanocrystals after the treatment with CO 2 .A fter the reduction in H 2 ,t he peak intensity for CO* species was weakened for fct-PdFe nanocrystals,i ndicating the consumption of CO.M eanwhile, the peak for dissociated O* species disappeared, demonstrating the reversible oxidation-reduction process for Fe species (Figure 3b). In comparison, the peak at 530.0 eV for dissociated O* species still remained for fcc-PdFen anocrystals, which was ascribed to the irreversible oxidation of Fe species.…”

Modification of Ti‐doped Hematite Photoanode with Quasi‐molecular Cocatalyst: A Comparison of Improvement Mechanism Between Non‐noble and Noble Metals

“…[8] However, the low conductivity and short hole diffusion distance ( � 4-6 nm) of hematite result in severe recombination of photo-induced carriers, and the sluggish OER kinetics on the surface restrict the smooth process of the surface water oxidation reaction. [9][10][11] To boost the PEC performance of hematite, a variety of modification methods have been researched and summarized, such as morphology design, [12] metal and nonmetal doping, [13,14] heterojunction construction, [15,16] surface plasmon resonance effect, [17] and cocatalyst loading. [18][19][20][21] Metal-doping is proved to be a simple but effective way to improve the low conductivity of hematite, of which the Ti doping as one of n-type doping (such as Ti 4 + , Sn 4 + , and Pt 4 + ) is a promising strategy by improving the donor concentration and charge transfer.…”

Hybrid photoanodes for water oxidation combining a molecular photosensitizer with a metal oxide oxygen-evolving catalyst

“…Intense researches are devoted to the development of photoelectrodes solely based on inorganic semiconductor (SC) materials, 2,7,11,15 but they face the difficulty of having a SC that can both effectively absorb visible light and display conduction and valence bands (denoted CB and VB, respectively) with adequate energy levels to catalyze OER for photoanodes and HER for photocathodes. Some PECs using SCs based on metal oxides (WO 3 , BiVO 4 , Fe 2 O 3 and CuBi 2 O 4 ) 4,7,[20][21][22][23][24] or oxynitrides (TaON, LaTiO 2 N and SrNbO 2 N) [25][26][27][28] for the photoanodes, and on p-type chalcogenides (CdTe, CuIn 1-x Ga x Se 2 ) 29,30 or metal oxides (p-Cu 2 O) [31][32][33][34] for the photocathodes, do operate under visible light. Nevertheless their STH conversion efficiency remains below 10%, the threshold for commercial applications.…”