scholarly journals Preparation of Ag nanoparticles by spark ablation in gas as catalysts for electrocatalytic hydrogen production

RSC Advances ◽  
2020 ◽  
Vol 10 (63) ◽  
pp. 38583-38587
Author(s):  
Junda Lu ◽  
Jia Guo ◽  
Shihao Song ◽  
Guangfa Yu ◽  
Hui Liu ◽  
...  

Spark ablation in gas (SAG) technology has the characteristics of being green, fast quenching, fast dynamics and specializes in producing metallic nanoparticles with a clean surface, small size, and abundant defects.

2022 ◽  
Author(s):  
Xiyu Deng ◽  
Xinya Kuang ◽  
Jiyang Zeng ◽  
Baoye Zi ◽  
Yiwen Ma ◽  
...  

Abstract Photocatalytic water splitting is considered to be a feasible method to replace traditional energy. However, most of the catalysts have unsatisfactory performance. In this work, we used a hydrothermal process to grow Ag nanoparticles in situ on g-C3N4 nanosheets, and then a high performance catalyst (Ag- g-C3N4) under visible light was obtained. The Ag nanoparticles obtained by this process are amorphous and exhibit excellent catalytic activity. At the same time, the local plasmon resonance effect of Ag can effectively enhance the absorption intensity of visible light by the catalyst. The hydrogen production rate promote to 1035 μmol g-1h-1 after loaded 0.6 wt% of Ag under the visible light, which was 313 times higher than that of pure g-C3N4 (3.3μmol g-1h-1). This hydrogen production rate is higher than most previously reported catalysts which loaded with Ag or Pt. The excellent activity of Ag- g-C3N4 is benefited from the Ag nanoparticles and special interaction in each other. Through various analysis and characterization methods, it is shown that the synergy between Ag and g-C3N4 can effectively promote the separation of carriers and the transfer of electrons. Our work proves that Ag- g-C3N4 is a promising catalyst to make full use of solar energy.


2021 ◽  
Vol 32 ◽  
Author(s):  
Lam Dinh Nguyen

Light scattering by noble metallic nanoparticles are of interest for a variety of applications due to the large electromagnetic field enhancement that occurs in the vicinity of the metal surface, and the dependence of the resonance photon energy on the nanoparticle size, shape, local dielectric environment, and material. Here, the influences of electromagnetic scattering by Au and Ag nanoparticles placed atop compound solar cells on optical absorption and photocurrent generation were investigated based on the variation in the noble nanoparticle densities. The results indicated that the short-circuit current and power conversion efficiency were strongly affected by the density and material of the noble nanoparticles. The great improvement of 28% in power conversion efficiency can be obtained with Au nanoparticle density of 2\(\times\)108 cm-2. This improvement can be attributed to light scattering, light trapping, and surface roughness by noble nanoparticles. Furthermore, Au nanoparticles showed more efficient in solar cell power conversion efficiency improvement than Ag nanoparticles did although density of Au nanoparticle was lower than that of Ag nanoparticles.


2016 ◽  
Vol 6 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Zhi Jiang ◽  
ZheYu Zhang ◽  
Wenfeng Shangguan ◽  
Mark A. Isaacs ◽  
Lee J. Durndell ◽  
...  

Pt photodeposition over titania in the presence of high methanol concentrations promotes the genesis of highly dispersed, metallic nanoparticles, active for photocatalytic hydrogen production.


Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1501
Author(s):  
Arina N. Suboch ◽  
Olga Y. Podyacheva

Bamboo-like nitrogen-doped carbon nanotubes (N-CNTs) were used to synthesize supported palladium catalysts (0.2–2 wt.%) for hydrogen production via gas phase formic acid decomposition. The beneficial role of nitrogen centers of N-CNTs in the formation of active isolated palladium ions and dispersed palladium nanoparticles was demonstrated. It was shown that although the surface layers of N-CNTs are enriched with graphitic nitrogen, palladium first interacts with accessible pyridinic centers of N-CNTs to form stable isolated palladium ions. The activity of Pd/N-CNTs catalysts is determined by the ionic capacity of N-CNTs and dispersion of metallic nanoparticles stabilized on the nitrogen centers. The maximum activity was observed for the 0.2% Pd/N-CNTs catalyst consisting of isolated palladium ions. A ten-fold increase in the concentration of supported palladium increased the contribution of metallic nanoparticles with a mean size of 1.3 nm and decreased the reaction rate by only a factor of 1.4.


2021 ◽  
Author(s):  
Sophie Camelio ◽  
David Babonneau ◽  
Elliot Vandenhecke ◽  
Guy Louarn ◽  
Bernard Humbert

In line with the SHINERS approach, in which Raman amplification is provided by metallic nanoparticles with an ultrathin dielectric shell, we report on a SERS substrate consisting of lines of Ag nanoparticles embedded in dielectric surfaces.


Author(s):  
Shinji Angata ◽  
Eiichi Ide ◽  
Akio Hirose ◽  
Kojiro F. Kobayashi

We propose a novel bonding process using Ag metallo-organic nanoparticles as a new application of nanotechnologies. The average size of the Ag nanoparticle is approximately 11 nm, and each nanoparticle is covered with an organic shell. Usually, the agglomeration of metallic nanoparticles is unavoidable due to its large surface energy. However, on the account of the organic shell, these Ag nanoparticles exist individually, and once the organic shell has been removed, these Ag nanoparticles turn activated and abruptly agglomerate. We analyzed its thermal characteristics, applied the agglomerating of the nanoparticles to Cu-to-Cu joining, and researched the influence of the bonding condition, such as bonding pressure, temperature or holding time, upon the joint strengths. The joint strengths using the nanoparticles were 30–40 MPa, which is strong enough to be applied as a solder. In addition, it came to the conclusion that the strengths increased in accord with the aforesaid three parameters.


Sign in / Sign up

Export Citation Format

Share Document