Fabrication of Direct Z‐scheme α‐Fe₂O₃/FeVO₄ Nanobelts with Enhanced Photoelectrochemical Performance

Abstract

A direct Z‐scheme type α‐Fe2O3/FeVO4 heterostructured photocatalyst with novel nanobelt structure just like the leaves of bryophyllum pinnatum has been successfully synthesized for the first time via integrating a facile electrospinning with annealing procedure. The as‐prepared products are characterized by XRD, FT‐IR, XPS, SEM, TEM, HRTEM, BET, PL, TOC, HPLC, EIS, Micro‐Raman and UV‐vis absorbance spectroscopy.The photocatalytic activity of α‐Fe2O3/FeVO4 nanobelts evaluated by themethylene blue (MB) degradation under visible light irradiation could be ascribed to the extended light absorption and improved charge separation efficiency. A reasonable Z‐scheme photocatalytic mechanism is proposed on the basis of structural and electrochemical characterization, which could well explain the enhanced migration rate of photogenerated carriers in α‐Fe2O3/FeVO4 heterojunctions.

Recent progress in iron oxide based photoanodes for solar water splitting

“…The nanorods array was deposited by a hydrothermal route on Ti mesh and was followed by coating MgFe 2 O 4 through wet impregnation. FeVO 4 has also been coupled with Fe 2 O 3 as a direct z-scheme structure for photoelectrochemistry [170]. Zhang et al recently investigated FeVO 4 based photoanodes and discussed their intrinsic optoelectronic properties [171].…”

One-step preparation of RGO/Fe3O4–FeVO4 nanocomposites as highly effective photocatalysts under natural sunlight illumination

“…( 3 ), ( 4 )]. The photoinduced e – on the CB of Fe 3 O 4 can transfer to the VB of FeVO 4 , and then quickly recombine with the h + of FeVO 4 were achieved, which is favorable for higher separation rate of e – -h + pairs of the single photocatalyst and higher redox potential 59 , 60 . In this case, the e – accumulated in CB of FeVO 4 are taken by the RGO and then reduce O 2 into · O 2– [Eqs.…”

“…( 5 ), ( 6 )], while the h + in VB of Fe 3 O 4 VB are more positive potential and has sufficient oxidation capacity to oxidize OH – into · OH or react with pollutants molecules directly [Eqs. ( 7 – 9 )] 59 – 63 . These results imply the contribution of generated radicals in the degradation of MB and phenol to gives CO 2 and H 2 O.…”

Rational Fabrication of Hierarchical Z‐Scheme WO3/Bi2WO6 Nanotubes for Superior Photoelectrocatalytic Reaction

“…As shown in Figure a, the PL intensity of 550 °C‐WO 3 /Bi 2 WO 6 photocatalyst exhibits the strongest emission than that of 500 °C‐WO 3 /Bi 2 WO 6 and 600 °C‐WO 3 /Bi 2 WO 6 photocatalysts, respectively, which could be attributed to the high recombination rate between photoexcited electrons in CB of Bi 2 WO 6 and photoexcited holes in VB of WO 3 , suggesting that rich electrons in CB of WO 3 and holes in VB of Bi 2 WO 6 participate in the reaction to produce ⋅ O 2 − and ⋅ OH. Considering the above analysis, it turns out that the WO 3 /Bi 2 WO 6 heterostructures belong to typical Z‐Scheme photocatalytic system . The removal of 4‐NP by the as‐prepared photocatalysts was performed to disclose the photocatalytic activity.…”