Showing papers by "Akira Fujishima published in 2020"
TL;DR: The synthesized TiO2 and GO/TiO2 photocatalyst materials are used to study the photocatalytic degradation of salicylic acid under sunlight illumination.
114 citations
TL;DR: The final remarks point the ideal photocatalytic way for the effective prevention/eradication of microorganisms, considering the resistance that the microorganism could develop without the appropriate regulatory aspects for human and ecosystem safety.
Abstract: The approach of this timely review considers the current literature that is focused on the interface nanostructure/cell-wall microorganism to understand the annihilation mechanism. Morphological studies use optical and electronic microscopes to determine the physical damage on the cell-wall and the possible cell lysis that confirms the viability and microorganism death. The key parameters of the tailoring the surface of the photoactive nanostructures such as the metal functionalization with bacteriostatic properties, hydrophilicity, textural porosity, morphology and the formation of heterojunction systems, can achieve the effective eradication of the microorganisms under natural conditions, ranging from practical to applications in environment, agriculture, and so on. However, to our knowledge, a comprehensive review of the microorganism/nanomaterial interface approach has rarely been conducted. The final remarks point the ideal photocatalytic way for the effective prevention/eradication of microorganisms, considering the resistance that the microorganism could develop without the appropriate regulatory aspects for human and ecosystem safety.
111 citations
TL;DR: In this paper, the photocatalytic reduction of CO2 over the direct Bi4TaO8Cl/W18O49 (BiW) Z-scheme system, which is assembled from Bi 4TaO 8Cl nanosheet and nanosized W18O 49, is shown to be markedly enhanced by simple integration of the photocatinalytic process with external heating.
Abstract: All-solid-state Z-scheme systems are attracting increasing interest in artificial photosynthesis of solar fuel. Recent research has revealed that solid electron mediators facilitate shuttle of electrons and thereby enhance photocatalytic activity. However, for a mediator-free direct Z-scheme system, it still remains a challenge to promote the Z-scheme-type charge transfer at the interface. Herein, we report that the photocatalytic reduction of CO2 over the direct Bi4TaO8Cl/W18O49 (BiW) Z-scheme system, which is assembled from Bi4TaO8Cl nanosheet and nanosized W18O49, is markedly enhanced by simple integration of the photocatalytic process with external heating. The CO yield over a typical BiW Z-scheme system is increased by 87 times when the system temperature is increased from 298 K to 393 K. This yield via BiW photocatalysis at 393 K is higher than Bi4TaO8Cl photocatalysis at 298 K by a factor of 167. The superior performance of BiW Z-scheme system at elevated temperature is believed to result from the thermo-enhanced shuttle of electron from W18O49 to Bi4TaO8Cl. Moreover, this BiW Z-scheme enables long-lasting catalytic reduction of CO2 in the dark after light irradiation, benefiting from the thermal release of stored electrons in W18O49 to the conduction band of Bi4TaO8Cl. This study suggests that photothermal synergy can enhance the Z-scheme behavior, providing a promising means for designing photothermal catalysts for the solar-catalytic reduction of CO2 to fuel.
110 citations
TL;DR: The SPP‐treated TiO2 exhibits a 300 times higher conversion rate for CO2 reduction under solar light irradiation and a 7.5 times higher removal rate of acetaldehyde under UV light irradation, suggesting the effectiveness of the proposed strategy to enhance the photoactivity of colored wide‐bandgap oxides for energy and environmental applications.
Abstract: Colored wide-bandgap semiconductor oxides with abundant mid-gap states have long been regarded as promising visible light responsive photocatalysts. However, their catalytic activities are hampered by charge recombination at deep level defects, which constitutes the critical challenge to practical applications of these oxide photocatalysts. To address the challenge, a strategy is proposed here that includes creating shallow-level defects above the deep-level defects and thermal activating the migration of trapped electrons out of the deep-level defects via these shallow defects. A simple and scalable solution plasma processing (SPP) technique is developed to process the presynthesized yellow TiO2 with numerous oxygen vacancies (Ov), which incorporates hydrogen dopants into the TiO2 lattice and creates shallow-level defects above deep level of Ov, meanwhile retaining the original visible absorption of the colored TiO2. At elevated temperature, the SPP-treated TiO2 exhibits a 300 times higher conversion rate for CO2 reduction under solar light irradiation and a 7.5 times higher removal rate of acetaldehyde under UV light irradiation, suggesting the effectiveness of the proposed strategy to enhance the photoactivity of colored wide-bandgap oxides for energy and environmental applications.
89 citations
TL;DR: In this article, a WS2-WS2 hybrid was synthesized via a facile and scalable two-step hydrothermal strategy combined with selective etching, which was proved to be efficient and durable electrocatalyst for hydrogen evolution in alkaline medium.
34 citations
TL;DR: In this article, the response of the reduced graphene oxide (RGO) and SnO2 nanohybridges was systematically tailored towards H2S, NO2 and H2 gases.
33 citations
TL;DR: In this article, solution plasma is utilized to activate the as-synthesized decahedral BiVO4 leading to a 1.5-fold higher oxygen evolution rate from water oxidation under visible light.
23 citations
TL;DR: In this article, a one-pot synthesis of anatase/bronze-type ((A/B)-TiO2) and carbon dots (CDs) via a simple solvothermal method using only TiCl4 and ethylene glycol was reported.
13 citations
TL;DR: In this paper, a mesoporous TiO2/BDD hybrid electrode was used for an advanced oxidation process (AOP), in which hydroxy radicals with stronger oxidative power (standard oxidation potential: 2.85 V vs. NHE) are formed using a combination of ozone, photocatalyst, and UV.
Abstract: Boron-doped diamond (BDD) electrodes have a wide potential window and can produce ozone by water electrolysis at high voltage. Though ozone has strong oxidative power (standard oxidation potential: 2.07 V vs. NHE), it cannot decompose certain types of recalcitrant organic matter completely. We developed an advanced oxidation process (AOP), in which hydroxy radicals with stronger oxidative power (standard oxidation potential: 2.85 V vs. NHE) are formed using a combination of ozone, photocatalyst, and UV. In this study, we fabricated a mesoporous TiO2/BDD hybrid electrode and examined its potential for AOPs. A synergetic effect between electrochemical water treatment and photocatalytic water treatment was observed with the hybrid electrode that did not occur with the BDD electrode.
11 citations
TL;DR: In this paper, a higher monomeric precursor for synthesizing improved micro-and electronic structure possessing graphitic carbon nitride (g-CN) was prepared by high-concentrated sulfuric acid (SA) treatment of bulk type g-CN.
Abstract: Modifying the physical, chemical structures of graphitic carbon nitride (g-CN) to improve its optoelectronic properties is the most efficient way to meet a high photoactivity for clean and sustainable energy production. Herein, a higher monomeric precursor for synthesizing improved micro-and electronic structure possessing g-CN was prepared by high-concentrated sulfuric acid (SA) treatment of bulk type g-CN (BCN). Several structural analyses show that after the SA treatment of BCN, the polymeric melon-based structure is torn down to cyameluric or cyanuric acid-based material. After re-polycondensation of this material as a precursor, the resulting g-CN has more condensed microstructure, carbon and oxygen contents than BCN, indicating that C, O co-doping by corrosive acid of SA. This g-CN shows a much better visible light absorption and diminished radiative charge recombination by the charge localization effect induced by heteroatoms. As a result, this condensed C, O co-doped g-CN shows the enhanced photocatalytic hydrogen evolution rate of 4.57 µmol/h from water under the visible light (>420 nm) by almost two times higher than that of BCN (2.37 µmol/h). This study highlights the enhanced photocatalytic water splitting performance as well as the provision of the higher monomeric precursor for improved g-CN.
11 citations
TL;DR: In this paper, ammonium ions were formed by electrochemical oxidation of urea with a boron-doped diamond (BDD) electrode, which was used together with a mesoporous titanium dioxide photocatalyst.
Abstract: Ammonium ions were formed by electrochemical oxidation of urea with a boron-doped diamond (BDD) electrode. Almost complete decomposition of urea was achieved. When the BDD electrode was used together with a mesoporous titanium dioxide photocatalyst, the amount of ammonium ions produced increased.
31 Aug 2020
TL;DR: Y-doping in this work is a new and promising approach for synthesizing highly active HTN by producing the HTN/rutile/anatase heterostructure within the one-pot method.
Abstract: We have prepared yttrium (Y)-doped hydrogen titanate nanorods (HTN) by a microwave-assisted hydrothermal method. Y-doped HTN showed much improved photocatalytic activities for both H2 evolution and...
TL;DR: This study suggests that α-FeOOH known as rust can produce H2 by light induction, even though the conduction band edge was lower than the reduction potential of H+ to H2.
Abstract: Invited for the cover of this issue is Tetsuya Yamada, Ken-ichi Katsumata and co-workers at Tokyo Institute of Technology and Tokyo University of Science. The image depicts rust producing hydrogen and purifying the pollutants at the same time by photocatalytic reaction. Read the full text of the article at 10.1002/chem.201903642.
TL;DR: In this paper, a coral-like hematite (ATO-Fe2O3) photoanode was grown on macroporous SnO2:Sb substrates, forming a corallike Hematite, which exhibited a 150mV cathodic shift of onset relative to Fe 2O3 nanorods.
TL;DR: A mesoporous titania thin film with a pseudo-single-crystal framework was synthesized on a lanthanum aluminate singlecrystal substrate by a surfactant-assisted sol-gel method and liquid-phase epitaxial growth as discussed by the authors.
Abstract: A mesoporous titania thin film with a pseudo-single-crystal framework was synthesized on a lanthanum aluminate single-crystal substrate by a surfactant-assisted sol–gel method and liquid-phase epitaxial growth. The crystal lattices were well aligned within the titania framework. The highly energetic {001} facet was exposed on the top surface, which significantly enhanced the photocatalytic activity.