Enabling high low-bias performance of Fe2O3 photoanode for photoelectrochemical water splitting

Boosted Photoelectrochemical Seawater Splitting by CoOOH-Modified Ti-Fe2O3/In2O3 by Synergy of Electronic Modulation and Heterojunction Construction

“…With the loading of In 2 O 3 (Figure c,d), it is clear that the Fe 2p XPS spectra of TFI and TFIC shifted toward higher binding energies, suggesting that the electrons in the CB of Fe 2 O 3 were transferred to In 2 O 3 . In addition, similar results can also be found for Fe 2p and Ti 2p XPS spectra of TF, TFI, and TFC (Figures S8 and S9, Supporting Information), illustrating the existence of an internal electrical field in the interface with its direction from Fe 2 O 3 to In 2 O 3 semiconductor, which can accelerate the charge separation efficiency …”

“…The light contrast with a thickness of about 5 nm shows a lattice interplanar spacing of 0.292 nm (Figure c), which can be indexed to the (222) plane of In 2 O 3 , suggesting that In 2 O 3 nanolayers were successfully loaded on TF nanorods. Meanwhile, the distinct boundary between TF and In 2 O 3 in Figure a also revealed the formation of a heterojunction across the interface, which is beneficial for the charge transfer across the interface . In addition, it can be clearly observed that there exists an amorphous layer of ∼1 nm in the outer layer of nanorods, which is attributed to the deposition of a CoOOH ultrathin layer on the surface (Figure b).…”

“…No other phase related to titanium oxides can be observed, indicating that extrinsic Ti elements exist in the form of doping rather than as oxides. Moreover, new peaks located at 21.8, 30.6, 41.9, 45.9, and 60.8° can be observed after loaded with In 2 O 3 , corresponding to (211), (222), (332), (431), and (622) facets of In 2 O 3 (JCPDS no.71-2194), respectively, suggesting the successful loading of In 2 O 3 . After electrodeposition of the CoOOH layer, due to the lower loading content of CoOOH and the fact that CoOOH exists in the form of an amorphous ultrathin layer, no diffraction peaks related to CoOOH can be observed.…”

Influence of Successive Zirconium and Beryllium Codoping Strategies on Advancing Bulk and Surface Properties of Hematite Photoanodes for Boosting Photoelectrochemical Water Splitting

“…In the meantime, however, the application of hematite is also severely restricted by its short hole transfer distance (2−4 nm), poor charge separation efficiencies in the bulk and on the surface, and slow water oxidation kinetics. 3,4 Heteroatom doping, homo/heterojunction formation, morphology control, and cocatalyst deposition have subsequently been employed to alleviate this scenario. 5−8 Particularly, doping with nanostructured morphology is the most effective method for decreasing the recombination of photogenerated charge carriers in the bulk of hematite.…”

“…In this context, photoelectrochemical (PEC) splitting of water is regarded as one of the most capable stratagems for H 2 production, as it is a suitable energy source for an entirely carbon-free energy environment. , Hematite (α-Fe 2 O 3 ; HT) has been perceived as a potential photoanode material for PEC water oxidation due to its unique characteristics, including a suitable bandgap (2.1 eV), earth abundance, low cost, nontoxicity, and good chemical stability. In the meantime, however, the application of hematite is also severely restricted by its short hole transfer distance (2–4 nm), poor charge separation efficiencies in the bulk and on the surface, and slow water oxidation kinetics. , Heteroatom doping, homo/heterojunction formation, morphology control, and cocatalyst deposition have subsequently been employed to alleviate this scenario. − Particularly, doping with nanostructured morphology is the most effective method for decreasing the recombination of photogenerated charge carriers in the bulk of hematite …”