NiFe-LDH-Decorated Ti-Doped Hematite Photoanode for Enhancing Solar Water-Splitting Efficiency

Abstract

Ti-doped α-Fe2O3 nanorods were prepared by a facile hydrothermal method, followed by a NiFe-LDH catalyst that was electrodeposited on the doped α-Fe2O3 nanorods to structure an integrating photoanode Ti:Fe2O3/NiFe-LDH for improving solar PEC water-splitting efficiency. The structure and properties of electrode materials were characterized and the PEC properties of photoanodes were measured. The results show that the photocurrent density of the photoanode enhances 11.25 times at 1.23 V (vs RHE) and the IPCE value enhances 4.10 times at 420 nm compared with pristine α-Fe2O3. The enhancement is attributed to the separating of photogenerated electron–hole, the increase of carrier density, and the acceleration of the carrier transfer rate due to the dual action of doping and catalysis.

Recent Developments in Nickel-Based Layered Double Hydroxides for Photo(-/)electrocatalytic Water Oxidation

“…The introduction of a thin layer of NiFe-LDH resulted in a negative shift in the onset potential and a significant improvement in charge injection efficiency. Bai et al 236 employed a simple hydrothermal method to synthesize Ti-doped α-Fe 2 O 3 nanorods. These nanorods were then coated with a NiFe-LDH cocatalyst through electrodeposition, creating an integrated photoanode known as Ti (0.25%): Fe 2 O 3 /NiFe-LDH.…”

Rational Design of CoOOH/α-Fe2O3/SnO2 for Boosted Photoelectrochemical Water Oxidation: The Roles of Underneath SnO2 and Surface CoOOH

“…To date, many semiconductor metal oxides/oxynitrides, such as TiO 2 , BiVO 4 , WO 3 , α-Fe 2 O 3 , and AB­(O,N) 3 (A = Ba, Ca, and Sr; B = Ta and Nb) have been developed to optimize PEC capacity for the OER. − Among them, α-Fe 2 O 3 is considered to be a promising candidate with suitable band gap (∼2.1 eV), elemental abundance, and chemical stability in alkaline solution . Nevertheless, the PEC OER activity of α-Fe 2 O 3 is still limited by several intrinsic defects, like poor conductivity, short minority carrier lifetime, and poor surface OER kinetics . To address these problems, various strategies, including morphology control, heterojunction construction, bulk element doping, and oxygen evolution catalyst (OEC) loading, have been developed to improve the PEC water splitting of α-Fe 2 O 3 . − As OER takes place at surface of α-Fe 2 O 3 , OEC loading is regarded as an effective route.…”