photocatalytic nonadides
Angewandte
Chemie
Photocatalyis with Visible Light
Photocatalytic Nanodiodes for Visible-Light
Photocatalysis**
Hyun G. Kim, Pramod H. Borse, Wonyong Choi, and
Jae S. Lee*
Photocatalysts that respond to visible light (l < 400 nm) are needed to utilize the main part of the solar spectrum for production of hydrogen energy by splitting water,[1, 2] purification of water and air,[3] and other applications.[4] Traditional visible-light photocatalysts are either unstable upon illumination with light (e.g., CdS, CdSe)[5] or have low activity (e.g.,
WO3, Fe2O3).[6] Recently, some UV-active oxides functioned as visible-light photocatalysts by substitutional doping of metals (as in MTiO2 (M = Fe, V, Mn)[7] and NixIn1ÀxTaO4 [8]), reduction of TiO2 (as in TiOx (x < 2)),[9] and anion doping with
N, C, and S (as in TiO2ÀxNx,[10] TiO2ÀxCx,[11] TaON,[12] and
Sm2Ti2O5S2 [13]). However, these doped materials, in general, show a small absorption in the visible-light region, leading to low activities.[14] New and more efficient visible-light photocatalysts are needed to meet the requirements of future environmental and energy technologies driven by solar energy. Herein we describe a novel configuration of composite solids designated as photocatalytic nanodiodes (PCD). These contain nano-islands of p-type CaFe2O4 interfaced over a highly crystalline layered perovskite base lattice (n-type
PbBi2Nb1.9W0.1O9), yielding nanodimensional p–n junctions.
[*] Dr. H. G. Kim, Dr. P. H. Borse, Prof. W. Choi, Prof. J. S. Lee
Department of Chemical Engineering and
School of Environmental Science & Engineering
Pohang University of Science and Technology
San-31 Hyoja-dong, Pohang 790-784 (Korea)
Fax: (+ 81) 54-279-5528
E-mail: jlee@postech.ac.kr
[**] This work was supported by the Hydrogen Energy R&D Center, the
Research Center for Energy Conversion and Storage, the National
R&D Center for Nano Science and Technology, the National
Research Laboratory Program,
Chemie
Photocatalyis with Visible Light
Photocatalytic Nanodiodes for Visible-Light
Photocatalysis**
Hyun G. Kim, Pramod H. Borse, Wonyong Choi, and
Jae S. Lee*
Photocatalysts that respond to visible light (l < 400 nm) are needed to utilize the main part of the solar spectrum for production of hydrogen energy by splitting water,[1, 2] purification of water and air,[3] and other applications.[4] Traditional visible-light photocatalysts are either unstable upon illumination with light (e.g., CdS, CdSe)[5] or have low activity (e.g.,
WO3, Fe2O3).[6] Recently, some UV-active oxides functioned as visible-light photocatalysts by substitutional doping of metals (as in MTiO2 (M = Fe, V, Mn)[7] and NixIn1ÀxTaO4 [8]), reduction of TiO2 (as in TiOx (x < 2)),[9] and anion doping with
N, C, and S (as in TiO2ÀxNx,[10] TiO2ÀxCx,[11] TaON,[12] and
Sm2Ti2O5S2 [13]). However, these doped materials, in general, show a small absorption in the visible-light region, leading to low activities.[14] New and more efficient visible-light photocatalysts are needed to meet the requirements of future environmental and energy technologies driven by solar energy. Herein we describe a novel configuration of composite solids designated as photocatalytic nanodiodes (PCD). These contain nano-islands of p-type CaFe2O4 interfaced over a highly crystalline layered perovskite base lattice (n-type
PbBi2Nb1.9W0.1O9), yielding nanodimensional p–n junctions.
[*] Dr. H. G. Kim, Dr. P. H. Borse, Prof. W. Choi, Prof. J. S. Lee
Department of Chemical Engineering and
School of Environmental Science & Engineering
Pohang University of Science and Technology
San-31 Hyoja-dong, Pohang 790-784 (Korea)
Fax: (+ 81) 54-279-5528
E-mail: jlee@postech.ac.kr
[**] This work was supported by the Hydrogen Energy R&D Center, the
Research Center for Energy Conversion and Storage, the National
R&D Center for Nano Science and Technology, the National
Research Laboratory Program,