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Structure of PbBi2Nb2O9 and Its Cr-Doped Layered Perovskite System and Their Photocatalytic Activities
Abstract
In the search for efficient photocatalysis for water splitting under visible light, the effect of chromium doping in a (100) layered Aurivillius-phase perovskite material, PbBi2Nb2O 2, has been studied. The Cr-doped PbBi2Nb 2O9 showed three absorption edges: the main edge due to the oxide at 431 nm and shoulders due to the chromium ions at 470 nm and 600 nm, respectively. The Pt/Cr-doped PbBi2Nb2O9 photocatalyst was more active than the undoped PbBi2Nb 2Og for photocatalytic decomposition of water-methanol solution. This is attributed to Cr+ ions having an important role in increasing QYs in the PbBi2Nb2O9.
... Pt-loaded PBN prepared by solid state reaction showed pho- toactivity of H 2 evolution with a yield of 7.6 mmol?g ?1 ?h ?1 . [11] Cr 3C doped PBN [17] or W 6C doped PBN [18] showed higher quantum yield for H 2 and O 2 generation than undoped material under visible light irradiation. Up to date, solid state reaction is the most often used method to prepare PBN. ...
Single phase of PbBi2Nb2O9 nanoplates was successfully synthesized by a hydrothermal method for the first time, using Pb(NO3)2, Bi(NO3)3·5H2O and Nb2O5 as the starting materials and NaOH as the mineralizer. The influences of the reaction conditions on the phases and morphologies of the products were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Diffuse reflectance spectra (DRS) showed the band gap of as-synthesized PbBi2Nb2O9 was 2.79 eV. Meanwhile, the photocatalytic activity for the decolorization of methylene blue under ultraviolet light irradiation of PbBi2Nb2O9 plates was evaluated.
Triple-layer Aurivillius perovskites degrade tetracycline antibiotic and rhodamine B together in acidic aqueous solution. Primarily the superoxide radical generated via a semiconductor assisted dye sensitization process degrades the tetracycline.
The massive use of non-renewable energy resources by humankind to fulfill their energy demands is causing severe environmental issues. Photocatalysis is considered one of the potential solutions for a clean and sustainable future because of its cleanliness, inexhaustibility, efficiency, and cost-effectiveness. Significant efforts have been made to design highly proficient photocatalyst materials for various applications such as water pollutant degradation, water splitting, CO2 reduction, and nitrogen fixation. Perovskite photocatalyst materials are gained special attention due to their exceptional properties because of their flexibility in chemical composition, structure, bandgap, oxidation states, and valence states. The current review is focused on perovskite materials and their applications in photocatalysis. Special attention has been given to the structural, stoichiometric, and compositional flexibility of perovskite photocatalyst materials. The photocatalytic activity of perovskite materials in different photocatalysis applications is also discussed. Various mechanisms involved in photocatalysis application from wastewater treatment to hydrogen production are also provided. The key objective of this review is to encapsulate the role of perovskite materials in photocatalysis along with their fundamental properties to provide valuable insight for addressing future environmental challenges.
A visible light active double layered Aurivillius phase, stable and high efficient semiconductor PbBi2Nb2O9 [PBN] samples were prepared by different methods such as Solid-State Reaction method (SSR), modified Sol-Gel process (SG). Also we have investigated the structural, morphological and optical properties of PbBi2Nb2O9 samples. The structural, morphological and optical properties of the synthesized crystalline samples were studied by using powder X-Ray Diffraction, Field Emission Scanning Emission Microscopy (FE-SEM), High Resolution–Transmission Electron Microscopy (HR-TEM), UV–Visible Diffuse Reflectance Spectroscopy (UV-DRS), Photoluminescence (PL) spectroscopy, X-Ray Photoelectron Spectroscopy (XPS), Brunauer-Emmett-Teller (BET) techniques. The Photocatalytic activities of organic pollutants such as Methylene Blue, Methyl Orange, and Rhodamine-B were studied under visible light irradiation. Hence, this study would be a corridor with the better understanding of PBN with various organic pollutants as well as different preparation methods towards the high efficient photocatalytic performances for applications such as water purification, its related environmental applications etc.
Development of layered perovskites for sunlight-driven catalysis has gained a lot of attention in contemporary inorganic materials research. While the compositional modification of three-dimensional perovskites is ubiquitous, they are infrequent in case of layered perovskites particularly with the niobates when the perovskite layer thickness is low. We report here solid state synthesis of a series of lead-free double-layer Aurivillius niobates, LaBi2Nb1.5M0.5O9 (M = Cr, Mn, Fe, Co), by adopting a heterovalent coupled substitution strategy with SrBi2Nb2O9. Rietveld structure refinements of the compounds using P-XRD data suggests formation of 3dn transition metal incorporated double-layer Aurivillius niobates in the non-centrosymmetric A21am space group, isostructural with the parent. The compounds show optical absorption in the visible region with absorption tail extending up to ~ 650 nm and band gaps ranging from 2.25-2.94 eV. While the compounds show paramagnetic behaviour with no indication of magnetic phase transition or ordering in the temperature range 5-300 K, the Mn compound stabilizes with a low-spin (LS) configuration in contrast to all others (Cr, Fe and Co compounds), which adopt high-spin (HS) configuration. The stabilization of LS configuration (t2g4) for the Mn compound occurs with eg -> t2g electron redistribution due to the suppression of first-order Jahn-Teller (FOJT) distortion by the dominating second-order Jahn-Teller (SOJT) distortion of Nb5+ (4d0). The compounds exhibit photocatalytic Rhodamine B degradation at pH2 within 50 -110 minutes under natural sunlight-irradiation and remain stable after five consecutive degradation cycles maintaining the activity of the catalysts largely intact. The heterovalent coupled substitution strategy adopted herewith will open up possibilities for transforming many other UV-active layered niobates into sunlight-active compounds without using toxic Pb or expensive Ag, while the paramagnetic nature of the compounds will be helpful in post-catalytic magnetic separation of the catalysts. It is believed that the electronic instability of t2g3eg1 configuration of the Mn due to competing FOJT and SOJT effects may have far-reaching consequences in modifying their magneto-structural and electronic transport properties.
We show that layered oxyhalides PbBiO2X (X = Cl, Br, I) with a Sillén-type structure possess band levels appropriate for visible light-induced water splitting. Under visible light, PbBiO2Cl and PbBiO2Br with bandgap (BG) of 2.40 and 2.36 eV, respectively, stably oxidized water to O2 in the presence of an Fe³⁺ electron acceptor. A comparison with structurally related SrBiO2Cl and BaBiO2Cl (BG = 3.41 and 3.40 eV) combined with DFT calculations revealed a significant interaction between O 2p and Pb 6s orbitals leading to the upward shift of the valence band maximum in PbBiO2X as compared with (Sr,Ba)BiO2Cl. Z-scheme water splitting into H2 and O2 has been demonstrated in PbBiO2Cl as an O2-evolving photocatalyst, coupled with an appropriate H2-evolving photocatalyst in the presence of a Fe³⁺/Fe²⁺ redox mediator.
Orthorhombic phase BaFe2O4 powder was synthesized by using a solid state reaction method and investigated for its visible light photocatalytic properties. The crystallization of the structural phase was found to occur at a temperature above 1000 °C yielding a pure orthorhombic phase BaFe2O4 (SG- B b21m) at 1100 °C. The estimated band gap, as determined by UV-Vis diffuse reflectance studies, was ~1.9 eV (652 nm). A new material was designed and fabricated as Pt/RuO2/BaFe2O4 to enhance its photocatalytic activity. A very low (<1 wt% RuO2) co-catalyst doping over BaFe2O4 was important for achieving high photocatalytic efficiency. The newly designed system was investigated for photo-decomposition of isopropyl alcohol (IPA) and of water under visible light (≥420 nm). Its photocatalytic activity was significantly higher than that of platinized TiO2-xNx. A mechanism has been proposed to explain the photocatalytic behavior of the designed BaFe2O4 photocatalyst.
The substitution effect of Ti4+ at the Fe3+ site in the spinel-phase ZnFe2O4 system has been studied and further optimized to fabricate an efficient photocatalyst. The material doped with an electron donor (Ti+4), ZnFe2-xTixO4, with an optimum composition of x = 0.06 exhibited a unchanged band gap, which generated two times higher photocurrent and showed an enhanced quantum yield (upto 0.77%) for photodecomposition of a H2O-CH3OH mixture compared to the undoped material under a visible light (lambda >= 420 nm). In contrast, the material doped with very high concentration of Ti revealed deteriorated photochemical properties due to constituent impurity phases. The higher electron density caused by n-type doping seemed to be responsible for the more efficient charge separation in ZnFe2-xTixO4 (0.01 < x < 0.09), and hence, the high photocatalytic activity.
ZnFe2O4 with a spinel crystal structure was synthesized by using the solid-state reaction method. A single-phase ZnFe 2O4 was obtained in the temperature range of 900 - 1200 °C. The as-synthesized particles were agglomerates of crystals with an average size of 51.9 nm, as estimated from X-ray diffraction analysis. The band gap of the n-type semiconducting metal oxide, as determined by using UV-vis diffuse reflectance spectroscopy (UV-DRS) was found to be 1.90 eV (657 nm). The photocatalytic activity of ZnFe2O4 was investigated by using the photo-decomposition of isopropyl alcohol (IPA) under visible light (≥420 nm) and was found to be much higher than that of the well-known TiO2-xNx photocatalyst.
We studied the co-dopant (Fe-Cr) concentration dependence on the visible light photocatalytic activity of SrTiO3 for the photodecomposition of gaseous iso-propyl alcohol (IPA), as well as the photo reduction of water. For the first time co-doping of perovskite SrTiO3 is investigated for co-doping with Cr and Fe metal-ions at Ti substitutional site. Undoped SrTiO3, Cr doped SrTiO3, Fe doped SrTiO3 and co-doped SrTi1-xFe[x/2]Cr[x]O4 (0.01 <= x <= 0.2) were synthesized for the present study. The optimum concentration shows a maximum photodecomposition activity for IPA, as well as photocatalytic hydrogen generation under visible light (lambda > 420 nm). The study on the co-dopant concentration optimization was found to be one of the important ways for fabricating an efficient photocatalyst. The optimum co-dopant concentration seems to yield a favorable density of states in the band gap of SrTiO3, which otherwise may lead to recombination centers.
Solid state synthesis of two Sr-Fe-O systems viz. Sr7Fe10O22 and SrFe12O19 was attempted and they were investigated for their photocatalytic properties. Although, both the systems exhibited good cystallinity and optical properties, only Sr7Fe10O22 was found to be active for the photocatalytic decomposition of iso-propanol under visible light. It also yielded a significant quantum yield (similar to 1.7%) for photo-reduction of water under visible light irradiation, much better than titanium oxy-nitride samples. The inactiveness of SrFe12O19 was due to its unsuitable band energetics. The Sr7Fe10O22 acted more efficiently than TiO2-xNx due to its suitable band positions and high visible light photon absorptivity.
The Bi2O3 quantum dots decorated nitrogen doped Bi3NbO7 nanosheets (Bi2O3/N-Bi3NbO7) were successfully synthesized via a facile in situ hydrothermal process as a straightforward protocol. The peony-like N-Bi3NbO7 hierarchical architectures decorated with surface enrichment of Bi2O3 quantum dots were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectra, UV-vis diffuse reflectance spectrum and photoluminescence spectra. The as-prepared Bi2O3/N-Bi3NbO7 heterostructures exhibited higher photocatalytic activities in the decomposition of model pollutants under visible-light irradiation than N-Bi3NbO7 nanosheets in the absence of any expensive metal components and co-catalysts, which could be attributed to the enhanced light absorbance multiple reflections in the heterostructures, the enhanced photosensitizing effect of the surface enriched Bi2O3 quantum dots and the strong interaction between Bi2O3 and N-Bi3NbO7. Furthermore, the Bi2O3/N-Bi3NbO7 heterostructures exhibited strong durability that may be ascribed to the high hydrothermal stability of the flower-like structure and the inhibition of Bi2O3 leaching owing to its tight chemical bonding with N-Bi3NbO7 nanosheets.
We synthesized four different photocatalyst systems of Zn2TiO4, Zn2Ti1-xFexO4, Zn2Ti1-xCrxO4 (0 <= x < 0.8) and Zn2Ti0.9CryFe[0.1-y]O4 (0.02 < y < 0.08) by using a solid state reaction method. For the first time, the UV-active photocatalyst Zn2TiO4 was converted to a visible light active material by controlled doping/co-doping with Cr and Fe metal-ions at Ti substitutional sites, and investigated the structural, optical and photocatalytic water decomposition properties of that materials. The co-doping induces strong absorption bands (at lambda similar to 480 nm and lambda similar to 620 nm) within the Zn2TiO4 band gap. The optimum system of Zn2Ti0.9Cr0.05Fe0.05O4 yielded maximum H-2 generation. In contrast to the visible light inactivity of Fe- and Cr-doped Zn2TiO4, the H-2 production from co-doped samples under visible light irradiation increased till the optimum 'y' value. Consequently, here exists an optimal co-dopant concentration for efficient photocatalytic hydrogen production under visible light (lambda >= 420 nm).
A spinel crystal structure of ferrite containing zinc (ZnFe2O4) was synthesized by using the polymer complex method. A pure phase ZnFe2O4 was obtained at a relatively lower temperature of 900 degrees C. The as-synthesized nanoparticles are agglomerates of crystals with an average size of similar to 50 urn, as estimated from the X-ray diffraction analysis. The band gap of the n-type semiconducting metal oxide, as determined by using an ultraviolet-visible diffuse reflectance spectrometer was found to be 1.90 eV (653 nm). The photocatalytic activity of ZnFe2O4 was investigated by using the photoreduction of water under visible light (>= 420 nm), which was found to be much higher than that of the well-known TiO2-x,N-x photocatalyst. This superior performance is attributed to the larger surface area, the uniform and well-dispersed deposition of the Pt co-catalyst over the surface, and the small band gap of the chemically-prepared ferrite photocatalyst.
We studied the photophysical properties of metal-doped photocatalytic materials active under visible light irradiation in order to understand the operating principles. We synthesized chromium-doped nanocrystalline titanium oxide by using the sol-gel and the hydrothermal synthesis methods. After heat treatment for the samples, we characterized their structures and basic properties by using conventional X-ray diffraction patterns, UV-visible absorption spectra and high-resolution transmission emission microscope. The photoluminescence spectra in the visible region at room temperature were taken to study the photophysical properties of the synthesized nanoparticles.
The effect substitution of Ti4+ at the Fe4+ site in a CaFe2O4-MgFe2O4 bulk hetero-junction (BH) lattice photocatalyst was explored and the Ti ion concentration was optimized to fabricate an efficient photocatalyst. A BH consisting of an optimum dopant concentration (Ti+4) level of x = 0.03 exhibited an increased band gap and generated a 1.5 times higher photocurrent. The newly fabricated Ti ion doped photocatalyst showed an enhanced quantum yield (upto similar to 13.3%) for photodecomposition of a H2O-CH3OH mixture, as compared to its undoped BH counterpart under visible light (lambda a parts per thousand yen 420 nm). In contrast, the material doped with a very high Ti-dopant concentration displayed deteriorated photochemical properties. An efficient charge-separation induced by Ti-ion doping seems to be responsible for the higher photocatalytic activity in a doped bulk BH.
Highly donor-doped (110) layered perovskite materials with a generic composition of AmBmO3m+2 (m = 4, 5; A = Ca, Sr, La; B = Nb, Ti) loaded with nickel have been found to be efficient photocatalysts for overall water splitting with quantum yields as high as 23% under UV irradiation.
To investigate the effects of Nd and V doping on Bi4Ti3O12 (BIT), (Bi3.25Nd0.75)Ti3O12 (BNT) and (Bi3.25Nd0.75)(Ti2.97V0.03)O12 (BNTV) ceramics were prepared by using a solid state reaction method. Dielectric, ferroelectric and electrical properties were studied by using a complex dielectric constant, ferroelectric polarization-electric field (P − E) hysteresis loops and electrical conductivity, respectively. A strong low-frequency dielectric dispersion was remarkably decreased by Nd and V doping, and the remanent polarization of BNT and BNTV ceramics increased. Compared to that of BIT and BNT ceramics, the conductivity of BNTV ceramics decreased as much as two orders of magnitude. The Nd and V doping on BIT must give a lower conductivity to improve the ferroelectric properties.
Mg-doped WO3 with band gap energy of about 2.6 eV is a viable photocatalyst for visible light-induced water splitting in the presence of hole scavengers. The conduction band edge position of p-type Mg-doped WO3 was -2.7 V versus SCE at pH 12. By doping Mg on WO3, the conduction and valence band positions were shifted by 2.25 V negatively, leading to a conduction band edge position which was negative enough for H+ ions to be reduced thermodynamically, with little change in band gap energy. The negative shift in band position might be ascribed to lowering of the effective electron affinity of WO3 by doping Mg with a very low electron affinity.
To use solar irradiation or interior lighting efficiently, we sought a photocatalyst with high reactivity under visible light.
Films and powders of TiO2-xNxhave revealed an improvement over titanium dioxide (TiO2) under visible light (wavelength < 500 nanometers) in optical absorption and photocatalytic activity such as photodegradations
of methylene blue and gaseous acetaldehyde and hydrophilicity of the film surface. Nitrogen doped into substitutional sites
of TiO2 has proven to be indispensable for band-gap narrowing and photocatalytic activity, as assessed by first-principles calculations
and x-ray photoemission spectroscopy.
Although n-type titanium dioxide (TiO2) is a promising substrate for photogeneration of hydrogen from water, most attempts at doping this material so that it absorbs
light in the visible region of the solar spectrum have met with limited success. We synthesized a chemically modified n-type
TiO2 by controlled combustion of Ti metal in a natural gas flame. This material, in which carbon substitutes for some of the lattice
oxygen atoms, absorbs light at wavelengths below 535 nanometers and has a lower band-gap energy than rutile (2.32 versus 3.00
electron volts). At an applied potential of 0.3 volt, chemically modified n-type TiO2 performs water splitting with a total conversion efficiency of 11% and a maximum photoconversion efficiency of 8.35% when
illuminated at 40 milliwatts per square centimeter. The latter value compares favorably with a maximum photoconversion efficiency
of 1% for n-type TiO2biased at 0.6 volt.
Nb-doped Bi 4(Ti 1-xNb x) 3O 12 (BITN) and Bi 3.25La 0.75(Ti 1-xNb x) 3O 12 (BLTN) ceramics (x = 0, 0.01, 0.03, 0.05, 0.07 and 0.10) were prepared by a solid-state reaction method. Nb doping decreases the low-frequency dielectric dispersions, which indicates that oxygen vacancies and other defects are decreased. The dielectric behavior of BLTN ceramics shows a diffuse phase transition, and a frequency-dispersive dielectric maximum shows relaxor-like behaviors. Effects of Nb doping on different dielectric properties and phase transition behaviors in bismuth titanate and bismuth lanthanum titanate were investigated.
Under visible light irradiation (λ
= 420–500 nm), a tantalum oxynitride, TaON, functions as a stable and very efficient photocatalyst for oxidation of water into O2 with a sacrificial electron acceptor (Ag+).
Alkali tantalate ATaO3 (A = Li, Na, and K) photocatalysts with perovskite-like structure showed activities for water splitting into H2 and O2 under UV irradiation. When the alkali tantalates were prepared in the presence of excess alkali, their activities were increased by 1 to 2 orders of magnitude. Scanning electron microscopy and photoluminescence measurements indicated that the excess alkali in the preparation increased the crystal size of NaTaO3 formed and prevented formation of alkali defects in NaTaO3 powder by volatilization, resulting in an increase in the photocatalytic activity. A LiTaO3 photocatalyst showed the highest activity among the naked alkali tantalate photocatalysts prepared in the presence of excess alkali. On the other hand, the activity of a NaTaO3 photocatalyst was increased by 1 order of magnitude when a NiO cocatalyst was loaded. The NiO(0.05 wt %)/NaTaO3 photocatalyst produced H2 and O2 from pure water with rates of 3.39 and 1.58 mmol h-1, respectively. The apparent quantum yield was 20% at 270 nm. It was concluded that the high activity of the NiO/NaTaO3 photocatalyst was due to the suitable conduction band level for photogenerated electrons to transfer to the NiO cocatalyst and delocalization of excited energy which were dominated by the orbital constituting the conduction band (Ta5d) and the slightly distorted connection between TaO6 octahedra in perovskite structure.
TiO2 and SrTiO3 codoped with antimony and chromium showed intense absorption bands in the visible light region and possessed 2.2 and 2.4 eV of energy gaps, respectively. TiO2 codoped with antimony and chromium evolved O2 from an aqueous silver nitrate solution under visible light irradiation, while SrTiO3 codoped with antimony and chromium evolved H2 from an aqueous methanol solution. The activity of TiO2 photocatalyst codoped with antimony and chromium was remarkably higher than that of TiO2 doped with only chromium. It was due to that the charge balance was kept by codoping of Sb5+ and Cr3+ ions, resulting in the suppression of formation of Cr6+ ions and oxygen defects in the lattice which should work as effectively nonradiative recombination centers between photogenerated electrons and holes.
Photocatalytic behaviors of some modified layered compounds derived from RbPb2Nb3O10 which was an ion exchanger with perovskite structure were examined. Under visible light irradiation (>420 nm) RbPb2Nb3O10-based catalysts were found to evolve H-2 from an aqueous methanol solution. The rate of H-2 evolution was greatly enhanced by replacing Rb+ ions with H+ ions. Further increase of the activity was obtained by Pt-loading. When [Pt(NH3)4]Cl2 was used as a precursor for Pt-loading instead of H2PtCl4, much higher activity was observed. It was interpreted that in the former case reduced Pt particles were highly dispersed at interlayer spaces due to the intercalation of [Pt(NH3)42+] ions prior to the photoreduction, while Pt particles existed only at the external surface of the catalyst in the latter case. The proposed structures for both catalysts were directly supported by TEM and XPS measurements. Several kinds of alcohols (ethanol, 1-propanol, and 1-butanol) were also used as sacrificial reagents. Among them methanol was by far the most suitable one for H-2 evolution. This remarkable shape selectivity was attributed to the intercalation of reactants into the catalyst.
A Ti-based oxysulfide, Sm(2)Ti(2)S(2)O(5), was studied as a visible light-driven photocatalyst. Under visible light (440 nm < or = lambda < or = 650 nm) irradiation, Sm(2)Ti(2)S(2)O(5) with a band gap of approximately 2 eV evolved H(2) or O(2) from aqueous solutions containing a sacrificial electron donor (Na(2)S-Na(2)SO(3) or methanol) or acceptor (Ag(+)) without any noticeable degradation. This oxysulfide is, therefore, a stable photocatalyst with strong reduction and oxidation abilities under visible-light irradiation. The electronic band structure of Sm(2)Ti(2)S(2)O(5) was calculated using the plane-wave-based density functional theory (DFT) program. It was elucidated that the S3p orbitals constitute the upper part of the valence band and these orbitals make an essential contribution to the small band gap energy. The conduction and valence bands' positions of Sm(2)Ti(2)S(2)O(5) were also determined by electrochemical measurements. It indicated that conduction and valence bands were found to have satisfactory potentials for the reduction of H(+) to H(2) and the oxidation of H(2)O to O(2) at pH = 8. This is consistent with the results of the photocatalytic reactions.
Green titana: Carbon-doped titanium dioxide, supported onto filter paper, photocatalyzes the gas-phase degradation of the atmospheric pollutants benzene (a), acetaldehyde (b) and carbon monoxide
Broccoli belongs to a group of cruciferous vegetables characterized by its content of glucosinolates, secondary metabolites that, upon hydrolysis, release bioactive isothiocyanates (ITCs). Sulforaphane, the major ITC from broccoli, is believed to protect the body from cancer by induction of detoxification enzymes such as quinone reductase (QR). Sulforaphane provides powerful protection against carcinogenesis, mutagenesis, and other forms of toxicity by electrophiles and reactive forms of oxygen. The purpose of this study was to investigate the effects of processing methods on the ability of broccoli to induce QR in various rat tissues. Male F344 rats (four per group) received an AIN 76B-40 diet containing either 0% or 20% broccoli processed by different methods (dehydrated, freeze-dried, or freeze-dried and hydrolyzed) for 5 days. Colon tissues of rats receiving dehydrated, freeze-dried, and hydrolyzed broccoli diets showed QR induction of 9.1-, 10.5-, and 6.4-fold, respectively. Induction of QR by dehydrated broccoli in the liver and kidney was significantly less robust than in colon, being 2.3- and 1.6-fold over control, respectively. These results suggest that freeze-drying and dehydration are promising approaches for providing the public with the functional benefits of broccoli consumption.
(Chemical Equation Presented) Oxidative decomposition of toxic pollutants (such as acetaldehyde and isopropyl alcohol), decomposition of water, and photocurrent generation can all be achieved with visible light. Nano-islands of p-type CaFe2O4 interfacing with bulk n-type PbBi 2Nb1.9W0.1O9 (shown) form photocatalytic nanodiodes that demonstrate high stability and high activity for such applications.
- H Kato
- A Kudo
H. Kato and A. Kudo, J. Phys. Chem. B 105, 4285
(2001).
- S U M Khan
- M Al-Shahry
S. U. M. Khan, M. Al-Shahry and W. B. Jr. Ingler, Science 297, 2243 (2002).
- Z Zou
- J Ye
- K Sayama
- H Arakawa
Z. Zou, J. Ye, K. Sayama and H. Arakawa, Nature 424,
625 (2002).
- K Domen
- A Kudo
- A Shinozaki
K. Domen, A. Kudo and A. Shinozaki, Chem. Commun.
356 (1986).
- G Hitoki
- T Takata
- J Kondo
- M Hara
- H Kobayashi
- K Domen
G. Hitoki, T. Takata, J. Kondo, M. Hara, H. Kobayashi
and K. Domen, Chem. Commun. 1698 (2002).
- J S Kim
- C W Ahn
- H J Lee
J. S. Kim, C. W. Ahn and H. J. Lee, J. Korean Phys.
Soc. 46, 140 (2005).
- J S Kim
- M S Jang
- I W Kim
- H J Lee
- K S Lee
J. S. Kim, M. S. Jang, I. W. Kim, H. J. Lee and K. S.
Lee, J. Korean Phys. Soc. 47, S280 (2005).
- R Asahi
- T Ohwaki
- K Aoki
- Y Taga
R. Asahi, T. Ohwaki, K. Aoki and Y. Taga, Science 293,
269 (2001).
- G C Ge
- A M Roy
- S S Bhattacharya
G. C. Ge, A. M. Roy and S. S. Bhattacharya, Int. J.
Hydrogen Energy 19, 21 (1996).
- J Yoshimura
- Y Ebana
- J Kondo
- K Domen
- A Tanaka
J. Yoshimura, Y. Ebana, J. Kondo, K. Domen and A.
Tanaka, J. Phys. Chem. B 97, 1970 (1993).
- D W Hwang
- J Kim
- T J Park
- J S Lee
D. W. Hwang, J. Kim, T. J. Park and J. S. Lee, Catal.
Lett. 80, 53 (2002).
- H G Kim
- D W Hwang
- J Kim
- Y G Kim
- J S Lee
H. G. Kim, D. W. Hwang, J. Kim, Y. G. Kim and J. S.
Lee, Chem. Commun. 1077 (1999).
- D W Hwang
- H G Kim
- J S Jang
- S W Bae
- S M Ji
- J S Lee
D. W. Hwang, H. G. Kim, J. S. Jang, S. W. Bae, S. M.
Ji and J. S. Lee, Catal. Today 95, 845 (2004).
- H Kato
- A Kudo
H. Kato and A. Kudo, J. Phys. Chem. B 106, 5029
(2002).
- J S Kim
- I W Kim
J. S. Kim and I. W. Kim, J. Korean Phys. Soc. 46, 143
(2005).
- H G Kim
- D W Hwang
- J S Lee
H. G. Kim, D. W. Hwang and J. S. Lee, J. Am. Chem.
Soc. 126, 8913 (2004).