TY - JOUR
T1 - Electronic Structures and Photoanodic Properties of Ilmenite-type MTiO3 Epitaxial Films (M = Mn, Fe, Co, Ni)
AU - Yoshimatsu, K.
AU - Mashiko, H.
AU - Umezawa, N.
AU - Horiba, K.
AU - Kumigashira, H.
AU - Ohtomo, A.
N1 - Funding Information:
This work was partly supported by the Ministry of Education Culture, Sports, Science and Technology (MEXT) Elements Strategy Initiative to Form Core Research Center, MEXT Photon and Quantum Basic Research Coordinated Development Program, a Grant-in-Aid for Scientific Research (Nos. 15H03881 and 16H05983) from the Japan Society for the Promotion of Science Foundation. H.M. acknowledges financial support by JSPS Research Fellowships for Young Scientists and the Program for the MEXT Leading Graduate Schools Academy for Co-creative Education of Environment and Energy Science (ACEEES).
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/8/31
Y1 - 2017/8/31
N2 - We performed systematic study on electronic structures and photoelectrochemical (PEC) properties of ilmenite-type MTiO3 (M = Mn, Fe, Co, and Ni) thin-film photoanodes for water-oxidation reactions. Single-phase MTiO3 films were grown on α-Al2O3 substrates by using pulsed-laser deposition. Formation of the ilmenite-type structures and oxidation states of M2+Ti4+O3 were revealed by X-ray diffraction and X-ray absorption spectroscopy, respectively. The PEC performance in water was investigated by linear sweep voltammetry under Xe-lamp illumination and incident photon to current effciency measurements under monochromatic illumination. We found that NiTiO3 acted as the most effective photoanode among MTiO3. The mechanism of the different PEC performance was discussed from the viewpoint of the electronic structures investigated by photoemission spectroscopy and band calculation based on density functional theory. We revealed that the stronger hybridization between O 2p and M 3d states was responsible for the more efficient photoanodic activity among ilmenite-type MTiO3.
AB - We performed systematic study on electronic structures and photoelectrochemical (PEC) properties of ilmenite-type MTiO3 (M = Mn, Fe, Co, and Ni) thin-film photoanodes for water-oxidation reactions. Single-phase MTiO3 films were grown on α-Al2O3 substrates by using pulsed-laser deposition. Formation of the ilmenite-type structures and oxidation states of M2+Ti4+O3 were revealed by X-ray diffraction and X-ray absorption spectroscopy, respectively. The PEC performance in water was investigated by linear sweep voltammetry under Xe-lamp illumination and incident photon to current effciency measurements under monochromatic illumination. We found that NiTiO3 acted as the most effective photoanode among MTiO3. The mechanism of the different PEC performance was discussed from the viewpoint of the electronic structures investigated by photoemission spectroscopy and band calculation based on density functional theory. We revealed that the stronger hybridization between O 2p and M 3d states was responsible for the more efficient photoanodic activity among ilmenite-type MTiO3.
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U2 - 10.1021/acs.jpcc.7b06076
DO - 10.1021/acs.jpcc.7b06076
M3 - Article
AN - SCOPUS:85028662614
VL - 121
SP - 18717
EP - 18724
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 34
ER -