A Dawson‐Type Dirhenium(V)‐Oxido‐Bridged Polyoxotungstate: X‐ray Crystal Structure and Hydrogen Evolution from Water Vapor under Visible Light Irradiation

2008 ◽  
Vol 2008 (20) ◽  
pp. 3134-3141 ◽  
Author(s):  
Chika Nozaki Kato ◽  
Kazunobu Hara ◽  
Ayumi Hatano ◽  
Kazuhiro Goto ◽  
Tomonori Kuribayashi ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Water Vapor ◽  
Visible Light ◽  
Hydrogen Evolution ◽  
Visible Light Irradiation ◽  
Light Irradiation ◽  
X Ray

Hydrogen Production over Eosin Y-Sensitized Pt-Loaded Layered Lanthanum Niobate under Visible Light Irradiation

2013 ◽  
Vol 815 ◽  
pp. 567-573
Author(s):  
Xiao Pei Zhang ◽  
Yue Lin Wei ◽  
Shu Hong Chen ◽  
Jing Xu ◽  
Huang Zhao ◽  
...  
Keyword(s):  
Visible Light ◽  
Hydrogen Evolution ◽  
Visible Light Irradiation ◽  
Hydrogen Generation ◽  
Energy Dispersive Spectrometer ◽  
Light Irradiation ◽  
Eosin Y ◽  
X Ray Diffraction ◽  
Dye Sensitization ◽  
X Ray

A novel and highly efficient photocatalyst, Eosin Y-sensitized Pt-intercalated nanotube Pt/HLa Nb2O7, was found to be very active for hydrogen generation within triethanolamine (TEOA) solution as the electron donor under visible-light irradiation (λ420 nm). The photocatalysts were characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (DRS), scan electron microscope (SEM) and energy dispersive spectrometer (EDS). The results showed that the significant enhancement of photocatalytic activity was achieved via Pt intercalating and subsequent dye sensitization of Pt/HLaNb2O7. The highest rate for hydrogen evolution was 4.45 mmol·g-1·h-1under irradiation with a wavelength longer than 420 nm, and the probable mechanism of photosensitized hydrogen evolution have also been discussed.

scholarly journals Preparation of NiS/ZnIn2S4 as a superior photocatalyst for hydrogen evolution under visible light irradiation

2013 ◽  
Vol 4 ◽  
pp. 949-955 ◽  
Author(s):  
Liang Wei ◽  
Yongjuan Chen ◽  
Jialin Zhao ◽  
Zhaohui Li
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Visible Light ◽  
Hydrogen Evolution ◽  
Visible Light Irradiation ◽  
Light Irradiation ◽  
Co Catalyst ◽  
Photocatalytic Hydrogen Evolution ◽  
X Ray ◽  
Transmission Electron

In this study, NiS/ZnIn2S4 nanocomposites were successfully prepared via a facile two-step hydrothermal process. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Their photocatalytic performance for hydrogen evolution under visible light irradiation was also investigated. It was found that the photocatalytic hydrogen evolution activity over hexagonal ZnIn2S4 can be significantly increased by loading NiS as a co-catalyst. The formation of a good junction between ZnIn2S4 and NiS via the two step hydrothermal processes is beneficial for the directional migration of the photo-excited electrons from ZnIn2S4 to NiS. The highest photocatalytic hydrogen evolution rate (104.7 μmol/h), which is even higher than that over Pt/ZnIn2S4 nanocomposite (77.8 μmol/h), was observed over an optimum NiS loading amount of 0.5 wt %. This work demonstrates a high potential of the developing of environmental friendly, cheap noble-metal-free co-catalyst for semiconductor-based photocatalytic hydrogen evolution.

Ta-substituted SnNb2−xTaxO6 photocatalysts for hydrogen evolution under visible light irradiation

2015 ◽  
Vol 3 (2) ◽  
pp. 825-831 ◽  
Author(s):  
Chan Woo Lee ◽  
Hoon Kee Park ◽  
Sangbaek Park ◽  
Hyun Soo Han ◽  
Se Won Seo ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Visible Light ◽  
Hydrogen Evolution ◽  
Visible Light Irradiation ◽  
Solid State Reaction ◽  
Photophysical Properties ◽  
Light Irradiation ◽  
Photocatalytic Activities

Ta-substituted SnNb2−xTaxO6 was successfully prepared via a solid-state reaction to study the effect of Ta insertion in Nb sites on the crystal structure, photophysical properties, and photocatalytic activities for hydrogen evolution.

Cu Doped TiO2: Visible Light Assisted Photocatalytic Antimicrobial Activity and High Temperature Anatase Stability

2018 ◽  
Author(s):  
Snehamol Mathew ◽  
Priyanka Ganguly ◽  
Stephen Rhatigan ◽  
Vignesh Kumaravel ◽  
Ciara Byrne ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Density Functional ◽  
Anatase Phase ◽  
Sol Gel ◽  
Chemical Properties ◽  
Light Irradiation ◽  
Health Concern ◽  
Bacterial Inactivation ◽  
X Ray

Indoor surface contamination by microbes is a major public health concern. A damp environment is one potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO<sub>2</sub>) can effectively curb this growing threat.<b> </b>Metal-doped titania in anatase phase has been proved as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu) doped TiO<sub>2 </sub>(Cu-TiO<sub>2</sub>) was evaluated against <i>Escherichia coli</i> (Gram-negative) and <i>Staphylococcus aureus</i> (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO<sub>2 </sub>was carried out <i>via</i> sol-gel technique. Cu-TiO<sub>2</sub> further calcined at various temperatures (in the range of 500 °C – 700 °C) to evaluate the thermal stability of TiO<sub>2</sub> anatase phase. The physico-chemical properties of the samples were characterised through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV-visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO<sub>2</sub> was maintained well, up to 650 °C, by the Cu dopant. UV-DRS results suggested that the visible light absorption property of Cu-TiO<sub>2 </sub>was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasises the introduction of Cu<sup>+</sup> and Cu<sup>2+</sup> ions by replacing Ti<sup>4+</sup> ions in the TiO<sub>2</sub> lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9%) was attained in 30 mins of visible light irradiation by Cu-TiO<sub>2</sub>.

Semiconductor Photocatalysts for Solar-to-Hydrogen Energy Conversion: Recent Advances of CdS

2020 ◽  
Vol 16 ◽  
Author(s):  
Yuxue Wei ◽  
Honglin Qin ◽  
Jinxin Deng ◽  
Xiaomeng Cheng ◽  
Mengdie Cai ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Visible Light ◽  
Hydrogen Evolution ◽  
Water Splitting ◽  
Visible Light Irradiation ◽  
Noble Metals ◽  
Light Irradiation ◽  
Photocatalytic Hydrogen Evolution ◽  
Theoretical Design ◽  
Recent Developments

Introduction: Solar-driven photocatalytic hydrogen production from water splitting is one of the most promising solutions to satisfy the increasing demands of a rapidly developing society. CdS has emerged as a representative semiconductor photocatalyst due to its suitable band gap and band position. However, the poor stability and rapid charge recombination of CdS restrict its application for hydrogen production. The strategy of using a cocatalyst is typically recognized as an effective approach for improving the activity, stability, and selectivity of photocatalysts. In this review, recent developments in CdS cocatalysts for hydrogen production from water splitting under visible-light irradiation are summarized. In particular, the factors affecting the photocatalytic performance and new cocatalyst design, as well as the general classification of cocatalysts, are discussed, which includes a single cocatalyst containing noble-metal cocatalysts, non-noble metals, metal-complex cocatalysts, metal-free cocatalysts, and multi-cocatalysts. Finally, future opportunities and challenges with respect to the optimization and theoretical design of cocatalysts toward the CdS photocatalytic hydrogen evolution are described. Background: Photocatalytic hydrogen evolution from water splitting using photocatalyst semiconductors is one of the most promising solutions to satisfy the increasing demands of a rapidly developing society. CdS has emerged as a representative semiconductor photocatalyst due to its suitable band gap and band position. However, the poor stability and rapid charge recombination of CdS restrict its application for hydrogen production. The strategy of using a cocatalyst is typically recognized as an effective approach for improving the activity, stability, and selectivity of photocatalysts. Methods: This review summarizes the recent developments in CdS cocatalysts for hydrogen production from water splitting under visible-light irradiation. Results: Recent developments in CdS cocatalysts for hydrogen production from water splitting under visible-light irradiation are summarized. The factors affecting the photocatalytic performance and new cocatalyst design, as well as the general classification of cocatalysts, are discussed, which includes a single cocatalyst containing noble-metal cocatalysts, non-noble metals, metal-complex cocatalysts, metal-free cocatalysts, and multi-cocatalysts. Finally, future opportunities and challenges with respect to the optimization and theoretical design of cocatalysts toward the CdS photocatalytic hydrogen evolution are described. Conclusion: The state-of-the-art CdS for producing hydrogen from photocatalytic water splitting under visible light is discussed. The future opportunities and challenges with respect to the optimization and theoretical design of cocatalysts toward the CdS photocatalytic hydrogen evolution are also described.

CdS/Ag2S/g-C3N4 ternary composites with superior photocatalytic performance for hydrogen evolution under visible light irradiation

2021 ◽  
Vol 50 (9) ◽  
pp. 3253-3260 ◽  
Author(s):  
Shan Zhao ◽  
Junbiao Wu ◽  
Yan Xu ◽  
Xia Zhang ◽  
Yide Han ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Hydrogen Evolution ◽  
Visible Light Irradiation ◽  
Photocatalytic Performance ◽  
Light Irradiation ◽  
Synergic Effect

CdS/Ag2S/g-C3N4 ternary composites showed excellent photocatalytic performance toward H2 evolution. Their improved photocatalytic activity could be attributed not only to the synergic effect, but also to the introduction of Ag2S.

D–π–A-type triphenylamine dye covalent-functionalized g-C3N4 for highly efficient photocatalytic hydrogen evolution

2020 ◽  
Vol 10 (6) ◽  
pp. 1609-1618 ◽  
Author(s):  
Chao Zhang ◽  
Jiandong Liu ◽  
Xingliang Liu ◽  
Shiai Xu
Keyword(s):  
Reaction Mechanism ◽  
Visible Light ◽  
Hydrogen Evolution ◽  
Visible Light Irradiation ◽  
Photocatalytic Performance ◽  
Light Irradiation ◽  
Photocatalytic Hydrogen Evolution ◽  
Highly Efficient

Reaction mechanism for the higher photocatalytic performance of H2 production of g-C3N4NSs/TC1 under visible light irradiation (λ ≥ 400 nm).

Photocatalytic Degradation of Methylene Blue over Co-Ag3VO4 under Visible Light Irradiation

2011 ◽  
Vol 335-336 ◽  
pp. 1385-1390 ◽  
Author(s):  
Shuo Wiei Zhao ◽  
Hui Xu ◽  
Hua Ming Li ◽  
Yuan Guo Xu
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Absorption Edge ◽  
Diffuse Reflectance Spectroscopy ◽  
Dye Degradation ◽  
Light Irradiation ◽  
Experimental Conditions ◽  
X Ray

In order to improve the photocatalytic activity, Co was successfully loaded into Ag3VO4 by using impregnation process. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). The XRD and SEM–EDS analyses revealed that Co ion was dispersed on Ag3VO4. The DRS results indicated that the absorption edge of the Co–Ag3VO4 catalyst shifted to longer wavelength. The enhanced photocatalytic activity of Co–Ag3VO4 for Methylene Blue(MB) dye degradation under visible light irradiation was due to its wider absorption edge and higher separation rate of photo-generated electron and holes. In the experimental conditions, it is demonstrated that the MB was effectively degraded by more than 95% within 40 min when the Co–Ag3VO4 catalyst was calcined at 300°C with 1 wt.% Co content.

Sign in / Sign up

Export Citation Format

Share Document