title: Uniform Doping of Titanium in Hematite Nanorods for Efficient Photoelectrochemical Water Splitting.
abstract: Doping elements in hematite nanostructures is a promising approach to improve the photoelectrochemical (PEC) water-splitting performance of hematite photoanodes. However, uniform doping with precise control on doping amount and morphology is the major challenge for quantitatively investigating the PEC water-splitting enhancement. Here, we report on the design and synthesis of uniform titanium (Ti)-doped hematite nanorods with precise control of the Ti amount and morphology for highly effective PEC water splitting using an atomic layer deposition assisted solid-state diffusion method. We found that Ti doping promoted band bending and increased the carrier density as well as the surface state. Remarkably, these uniformly doped hematite nanorods exhibited high PEC performance with a pronounced photocurrent density of 2.28 mA/cm(2) at 1.23 V vs reversible hydrogen electrode (RHE) and 4.18 mA/cm(2) at 1.70 V vs RHE, respectively. Furthermore, as-prepared Ti-doping hematite nanorods performed excellent repeatability and durability; over 80% of the as-fabricated photoanodes reproduced the steady photocurrent density of 1.9-2.2 mA/cm(2) at 1.23 V vs RHE at least 3 h in a strong alkaline electrolyte solution.
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Degao
authors.initials: D
authors.lastname: Wang
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Huaican
authors.initials: H
authors.lastname: Chen
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Guoliang
authors.initials: G
authors.lastname: Chang
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Lin
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Yuying
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: ‡Chemistry Department, King Saud University, Riyadh 11451, Saudi Arabia.
authors.forename: Ali
authors.initials: A
authors.lastname: Aldalbahi
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Peng
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Wang
authors.affiliation: †Division of Physical Biology, and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Chunhai
authors.initials: C
authors.lastname: Fan
keywords: atomic layer deposition; hematite nanorod; photoelectrochemical; solid-state diffusion; uniform Ti doping