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Fe2TiO5 has attracted extensive attention as a promising photoanode for solar water splitting. However, its water splitting performance still needs to be improved. Here, a Zn2+-doped Fe2TiO5 photoanode decorated with a FeNi(OH)x cocatalyst was prepared by a two-step electrospray technique, and the photocurrent density of the resultant photoanode significantly increased by a factor of seven at 1.23 V vs. RHE compared to pristine Fe2TiO5, while the cathodic shift of the onset potential was up to 250 mV. The obvious improvement on the photoelectrochemical (PEC) performance can be attributed to the cooperative effect of heteroatom doping and cocatalyst deposition. The doping of Zn2+ optimizes electron transfer and promotes charge separation efficiency in the bulk of Fe2TiO5 films. Meanwhile, the FeNi(OH)x cocatalyst can accelerate oxygen evolution kinetics and suppress charge recombination at the electrode/electrolyte interface. Thus, combining doping with a cocatalyst by facile electrospray offers an effective strategy for the development of high-performance photoanodes. [ABSTRACT FROM AUTHOR]

Abstract: The structure and composition evolution of hydroxyapatite in bone and teeth play important roles on their strength and durability, especially of the local chemical environment of Ca evolution, that determines bone demineralization and osteoporosis. In this paper, we synthesized a series of Eu‐doped (2‐10%) hydroxyapatite nanorod via subcritical hydrothermal method at high temperature (220‐280 oC) with the doped ions fully occupied at Ca1‐site. The as‐synthesized samples are grown with uniform particle size and shape distribution. Crystal morphology formation mechanism has been discussed based on the Bravais–Friedel–Donnay–Harker method and crystal structure of hydroxyapatite. Powder X‐ray diffraction result and Pawley fitting of the diffraction pattern for Eu‐doped hydroxyapatite samples indicate a linear structure evolution with increasing doping level. FTIR spectra suggest the minimal structure change for Eu‐doped hydroxyapatite nanocrystals. Photoluminescent spectra of Ca10(PO4)6(OH)2:Eu indicates the doping of Eu happens at the Ca1‐site, which shows a concentration‐dependent emission intensity evolution behavior. Decay curves for the 5D0→7F2 transition of Eu3+ in each samples suggested a longer lifetime in our samples than the similar composition that prepared via other methods. The site‐selective occupancy of Eu‐doped hydroxyapatite luminescent phenomenon may serve as a potential indicator for monitoring the Ca‐loss in bones and teeth that caused osteoporosis in aging people. [ABSTRACT FROM AUTHOR]