In Situ Controllable Loading of Ultrafine Noble Metal Particles on Titania

Xie, Yun; Ding, Keqiang; Liu, Zhimin; Tao, Ranting; Sun, Zhenyu; Zhang, Hongye; An, Guimin

doi:10.1021/ja900447d

Cited by 137 publications

(81 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Plasma-enhanced impregnation has been used to improve the dispersion of Pt, resulting in enhanced photoactivity for hydrogen generation. [63,70] Xie et al [71] have developed a novel and simple method to load noble metals on TiO 2 in situ, through a redox reaction between the reductive Ti III oxide support and metal salt precursors. The metal was highly dispersed and its size could be well-controlled.…”

Section: Loading Tio 2 With Noble Metalsmentioning

confidence: 99%

“…[70] Furthermore, well-dispersed Pt particles can promote the separation of e À and h + and therefore show higher photoactivities. [71,79] , and ionic Pt under different preparation procedures and conditions. [80] A few works have been performed to clarify the state of the active component in photocatalytic degradation reactions, such as degradation of chlorinated organic compounds, carboxylic acid, alcohol, phenolics, and nitric oxide, [80][81][82][83] but no general conclusion could be drawn.…”

Section: Loading Tio 2 With Noble Metalsmentioning

confidence: 99%

See 1 more Smart Citation

Hydrogen Production over Titania‐Based Photocatalysts

et al. 2010

View full text Add to dashboard Cite

Because of their relatively high efficiency, high photostability, abundance, low cost, and nontoxic qualities, titania-based photocatalysts are still the most extensively studied materials for the photocatalytic production of hydrogen from water. The effects of the chemical and physical properties of titania, including crystal phase, crystallinity, particle size, and surface area, on its photoactivity towards hydrogen generation have been identified by various investigations. The high overpotential for hydrogen generation, rapid recombination of photogenerated electrons and holes, rapid reverse reaction of molecular hydrogen and oxygen, and inability to absorb visible light are considered the most important factors that restrict the photoactivity of titania, and strategies to overcome these barriers have been developed. These issues and strategies are carefully reviewed and summarized in this Minireview. We aim to provide a critical, up-to-date overview of the development of titania-based photocatalysts for hydrogen production, as well as a comprehensive background source and guide for future research.

show abstract

Section: Loading Tio 2 With Noble Metalsmentioning

confidence: 99%

Section: Loading Tio 2 With Noble Metalsmentioning

confidence: 99%

Hydrogen Production over Titania‐Based Photocatalysts

et al. 2010

View full text Add to dashboard Cite

show abstract

“…21 This in situ approach was relatively simple but exhibited low control over the metal particle size and dispersion. While the PVD and PP methods showed better potential to overcome these problems, they suffered from some inherent drawbacks, such as high cost and complicated operation.…”

mentioning

confidence: 99%

High-Efficiency Photoelectrocatalytic Hydrogen Generation Enabled by Palladium Quantum Dots-Sensitized TiO₂ Nanotube Arrays

et al. 2012

View full text Add to dashboard Cite

TiO 2 nanotube arrays (TNTAs) sensitized by palladium quantum dots (Pd QDs) exhibit highly efficient photoelectrocatalytic hydrogen generation. Vertically oriented TNTAs were prepared by a three-step electrochemical anodization. Subsequently, Pd QDs with uniform size and narrow size distribution were formed on TiO 2 nanotubes by a modified hydrothermal reaction (i.e., yielding nanocomposites of Pd QDs deposited on TNTAs, Pd@TNTAs). By exploiting Pd@TNTA nanocomposites as both photoanode and cathode, a substantially increased photon-to-current conversion efficiency of nearly 100% at λ = 330 nm and a greatly promoted photocatalytic hydrogen production rate of 592 μmol·h −1 ·cm −2 under 320 mW·cm −2 irradiation were achieved. The synergy between nanotubular structures of TiO 2 and uniformly dispersed Pd QDs on TiO 2 facilitated the charge transfer of photoinduced electrons from TiO 2 nanotubes to Pd QDs and the high activity of Pd QDs catalytic center, thereby leading to high-efficiency photoelectrocatalytic hydrogen generation. P hotoelectrocatalytic water splitting is widely recognized as one of the most promising routes to large-scale production of hydrogen as a potential fuel for renewable energy.1 Among the various catalysts, the noble metal palladium has attracted much attention as one of the most versatile candidates utilized in hydrogen-relevant reactions.2 In particular, Pd immobilized on diverse supports, including carbon, silicates, amorphous or mesoporous silica, and porous biomaterials or polymers, exhibits remarkable performance in organic transformations and especially coupling and hydrogenation reactions.3−6 Onedimensional highly ordered TiO 2 nanotube arrays (TNTAs) fabricated by electrochemical anodization have been demonstrated as a promising photoanode for use in photocatalytic water splitting and solar energy conversion with markedly improved efficiency.7−13 Modified TNTAs were found to possess attractive activities for photoelectrocatalytic water splitting.14,15 However, due to the fast recombination of photogenerated electrons and holes, it remains a major challenge to successfully capitalize on TNTAs for photocatalytic applications.It is well known that the catalytic properties of composites of transition metal particles and supporting materials depend heavily upon the metal particle size, dispersion, composition, etc. 16,17 In this context, it is of high importance to prepare such composites with uniform dispersion, tunable particle size, and narrow size distribution to promote their catalytic activities. 18Catalysts made of Pd nanoparticles supported on TNTAs (i.e., Pd@TNTA nanocomposites) are expected to enhance TiO 2 photocatalysis for hydrogen generation; this can be ascribed to their prominent charge-transfer and separation properties and stability against photocorrosion. 19 The latter contrasts sharply with most of semiconductors, such as CdS, which cause photocorrosion and are not suitable for water splitting.19 As the Fermi level of Pd is lower than that of TiO 2 , photoex...

show abstract

“…As detailed in the Experimental Section, the surface‐loaded sample was prepared by reacting preformed ceria intermediate nanorods (ceria/cerium hydroxide nanorods) with the K 2 PtCl 4 solution. Similar to our synthesis, this reaction has been known to load ultrafine Pt NPs on reduced oxide surfaces (Figure S3B, Supporting Information) 25, 26, 27. The encapsulated sample was prepared by simultaneously introducing K 2 PtCl 4 during the same time when ceria nanostructures were formed (Figure S4, Supporting Information).…”

Section: Resultsmentioning

confidence: 86%

Embedding Ultrafine and High‐Content Pt Nanoparticles at Ceria Surface for Enhanced Thermal Stability

Bian

et al. 2017

Advanced Science

View full text Add to dashboard Cite

Ultrafine Pt nanoparticles loaded on ceria (CeO2) are promising nanostructured catalysts for many important reactions. However, such catalysts often suffer from thermal instability due to coarsening of Pt nanoparticles at elevated temperatures, especially for those with high Pt loading, which leads to severe deterioration of catalytic performances. Here, a facile strategy is developed to improve the thermal stability of ultrafine (1–2 nm)‐Pt/CeO2 catalysts with high Pt content (≈14 wt%) by partially embedding Pt nanoparticles at the surface of CeO2 through the redox reaction at the solid–solution interface. Ex situ heating studies demonstrate the significant increase in thermal stability of such embedded nanostructures compared to the conventional loaded catalysts. The microscopic pathways for interparticle coarsening of Pt embedded or loaded on CeO2 are further investigated by in situ electron microscopy at elevated temperatures. Their morphology and size evolution with heating temperature indicate that migration and coalescence of Pt nanoparticles are remarkably suppressed in the embedded structure up to about 450 °C, which may account for the improved thermal stability compared to the conventional loaded structure.

show abstract

In Situ Controllable Loading of Ultrafine Noble Metal Particles on Titania

Cited by 137 publications

References 16 publications

Hydrogen Production over Titania‐Based Photocatalysts

Hydrogen Production over Titania‐Based Photocatalysts

High-Efficiency Photoelectrocatalytic Hydrogen Generation Enabled by Palladium Quantum Dots-Sensitized TiO₂ Nanotube Arrays

Embedding Ultrafine and High‐Content Pt Nanoparticles at Ceria Surface for Enhanced Thermal Stability

Contact Info

Product

Resources

About

In Situ Controllable Loading of Ultrafine Noble Metal Particles on Titania

Cited by 137 publications

References 16 publications

Hydrogen Production over Titania‐Based Photocatalysts

Hydrogen Production over Titania‐Based Photocatalysts

High-Efficiency Photoelectrocatalytic Hydrogen Generation Enabled by Palladium Quantum Dots-Sensitized TiO2 Nanotube Arrays

Embedding Ultrafine and High‐Content Pt Nanoparticles at Ceria Surface for Enhanced Thermal Stability

Contact Info

Product

Resources

About

High-Efficiency Photoelectrocatalytic Hydrogen Generation Enabled by Palladium Quantum Dots-Sensitized TiO₂ Nanotube Arrays