Ni doped amorphous FeOOH layer as ultrafast hole transfer channel for enhanced PEC performance of BiVO4.

[Display omitted] Bismuth vanadate (BiVO 4), as the potential and prospective photocatalyst, has been limited by the issue of poor separation and transfer of charge carrier for photoelectrocatalytic (PEC) water oxidation. Here, a significant increase of surface injection efficiency for BiVO 4 is realized by the rationally designed Ni doped FeOOH (Ni:FeOOH) layer growing on BiVO 4 photoanode (Ni:FeOOH/BiVO 4), in which doped Ni2+ can induce partial-charge of FeOOH to serve as ultrafast transfer channel for hole transfer and transportation at the semiconductor/electrolyte interface. In addition, the Ni:FeOOH/BiVO 4 shows the η surface value of 81.6 %, which is 3.28-fold and 1.47-fold of BiVO 4 and FeOOH/BiVO 4 , respectively. The photocurrent density of Ni:FeOOH/BiVO 4 is 4.21 mA cm−2 at 1.23 V vs. RHE, with the onset potential cathodically shifting 237 mV over BiVO 4 and a long-term stability for suppressing surface charge recombination. The UPS and UV–Vis spectra have confirmed the type-II band alignment between Ni:FeOOH and BiVO 4 for promoting carrier transfer. This facile and effective spin-coating method could deposit oxygen evolution catalysts (OECs) availably onto photoanodes with enhanced PEC water splitting. [ABSTRACT FROM AUTHOR]