Surface state modulation for size-controllable photodeposition of noble metal nanoparticles on semiconductors

For a comparative cytotoxicity study, nanoparticles of the noble metals Rh, Pd, Ag, Pt, and Au (spherical, average diameter 4 to 8 nm) were prepared by reduction in water and colloidally stabilized with poly(N-vinyl pyrrolidone) (PVP). Thus, their shape, size, and surface functionalization were all the same. Size and morphology of the nanoparticles were determined by dynamic light scattering (DLS), analytical disc centrifugation (differential centrifugal sedimentation, DCS), and high-resolution transmission electron microscopy (HRTEM). Cell-biological experiments were performed to determine the effect of particle exposure on the viability of human mesenchymal stem cells (hMSCs). Except for silver, no adverse effect of any of the metal nanoparticles was observed for concentrations up to 50 ppm (50 mg L−1) incubated for 24 h, indicating that noble metal nanoparticles (rhodium, palladium, platinum, gold) that do not release ions are not cytotoxic under these conditions.

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A universal approach to the synthesis of nanodendrites of noble metals

Nanoscale ◽

10.1039/c4nr00421c ◽

2014 ◽

Vol 6 (11) ◽

pp. 6173-6179 ◽

Cited By ~ 21

Author(s):

Yan Feng ◽

Xiaohong Ma ◽

Lin Han ◽

Zhijian Peng ◽

Jun Yang

Keyword(s):

Metal Nanoparticles ◽

Noble Metal ◽

Noble Metals ◽

Noble Metal Nanoparticles ◽

Universal Approach ◽

Dendritic Structures

A universal approach was demonstrated for the synthesis of noble metal nanoparticles with dendritic structures.

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A seed-mediated approach to the general and mild synthesis of non-noble metal nanoparticles stabilized by a metal–organic framework for highly efficient catalysis

Materials Horizons ◽

10.1039/c5mh00125k ◽

2015 ◽

Vol 2 (6) ◽

pp. 606-612 ◽

Cited By ~ 33

Author(s):

Yu-Zhen Chen ◽

Linfeng Liang ◽

Qihao Yang ◽

Maochun Hong ◽

Qiang Xu ◽

...

Keyword(s):

Metal Nanoparticles ◽

Noble Metal ◽

Noble Metals ◽

Metal Organic Framework ◽

Catalytic Performance ◽

Noble Metal Nanoparticles ◽

Mild Conditions ◽

Highly Efficient ◽

Metal Organic ◽

Seed Mediated

A novel noble metal-seed-mediated approach to reduce non-noble metals under mild conditions to afford non-noble metal NPs with superior catalytic performance.

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Visible Light-Mediated Sustainable Antibacterial Activity and Osteogenic Functionality of Au and Pt Multi-Coated TiO2 Nanotubes

Materials ◽

10.3390/ma14205976 ◽

2021 ◽

Vol 14 (20) ◽

pp. 5976

Author(s):

Kyoung-Suk Moon ◽

Young-Bum Park ◽

Ji-Myung Bae ◽

Eun-Joo Choi ◽

Seung-Han Oh

Keyword(s):

Antibacterial Activity ◽

Visible Light ◽

Metal Nanoparticles ◽

Noble Metal ◽

Noble Metals ◽

Human Mesenchymal Stem Cells ◽

Antibacterial Activities ◽

Titania Nanotubes ◽

Noble Metal Nanoparticles ◽

Low Level Laser Therapy

The visible light reactions of noble metal-based photocatalysts have been increasingly utilized to investigate their antibacterial activities. Furthermore, the photoreactions at various visible light wavelengths for specific combinations of titania nanotubes and noble metal nanoparticles have been found to promote osteogenic functionality. In this investigation, a novel multi-coating combination of noble metals (gold and platinum) on titania nanotubes was assessed using plasmonic photocatalysis and low-level laser therapy at 470 and 600 nm. The results showed that this coating on the nanotubes promoted antibacterial activity and osteogenic functionality. The order in which the gold and platinum coatings were layered onto the titania nanotubes strongly affected the osteogenic performance of the human mesenchymal stem cells. These results have identified a new approach for the development of efficient novel combinations of noble metal nanoparticles and titania nanotubes with visible light responses, sustainable antimicrobial activity, and osteogenic functionality.

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The Influence of the Ratio of Au and Pt Nanoparticles in Ternary Composites with TiO2

Metals ◽

10.3390/met11040628 ◽

2021 ◽

Vol 11 (4) ◽

pp. 628

Author(s):

Boglárka Hampel ◽

Lucian Baia ◽

Klara Hernadi ◽

Zsolt Pap

Keyword(s):

Oxalic Acid ◽

Metal Nanoparticles ◽

Noble Metal ◽

Noble Metals ◽

Diffuse Reflectance Spectroscopy ◽

Uv Light ◽

Production Capacity ◽

Pt Nanoparticles ◽

Noble Metal Nanoparticles ◽

Sacrificial Agent

In the present work, ternary composites were synthesized from commercial titanias (Evonik Aeroxide P25, Aldrich anatase—AA and Aldrich rutile—AR) and two noble metals (gold and platinum). This research focuses on the composition of the photocatalysts, especially on the noble metals. The ratio between the noble metals varies from 0.25 to 0.75% in each composite for each noble metal. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and diffuse reflectance spectroscopy (DRS) measurements were carried out to investigate the structural and optical properties. From the TEM, it can be observed that the particle sizes of the noble metals were between 1 and 4 nm, while the (anatase and rutile) crystals of P25 were 20–40 nm. The XRD showed that the semiconductors’ composition remained unchanged during/after the deposition of noble metal nanoparticles. By the DRS measurements, using the Kubelka–Munk equation, it can be concluded that the deposition of the noble metal nanoparticles resulted the decrease of the bandgap energies of the titanias. The photocatalytic activity was investigated under the irradiation of UV light. Oxalic acid and salicylic acid were used as model pollutants. The hydrogen production capacity was investigated as well, where the sacrificial agent was oxalic acid, and UV irradiation was used.

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