First‐principles investigation of the structure, mechanical and hydrogen adsorption behavior of NiPt nanoparticle

Abstract

Noble metal nanoparticles are attractive catalytic materials because of the excellent physical and chemical properties. However, the structural stability and hydrogenation mechanism of NiPt nanoparticle are not entirely unclear due to the structural feature. We apply the first-principles calculations to study the structure, mechanical and electronic properties of NiPt nanoparticle. In particular, the hydrogenation mechanism of NiPt is studied. Here, four nanoparticles (line, ladder, saw tooth and triangular) and three crystal structures (cubic and tetragonal) are considered. The calculated results show that the crystal NiPt is more thermodynamically stable than the nanoparticles. We first find that the NiPt with tetragonal structure (P4/mmm) is a stable phase among these crystal structures. The calculated lattice parameters of the tetragonal NiPt are a = 2.731 Å and c = 3.664 Å. In addition, the tetragonal structure is mechanically stable. In particular, it is found that the hydrogen (H) occupies the octahedral interstice site in comparison to the tetrahedral interstice site. Essentially, the hydrogenation behavior of NiPt is attributed to the strong hybridization between H and NiPt.

Influence of N‐vacancy on the electronic and optical properties of bulk GaN from first‐principles investigations

“…Here, two key optical properties: dielectric function and optical adsorption spectra are studied. [76][77][78][79] Figure 4 shows the calculated dielectric function diagram of the bulk GaN with the N-vacancies. Here, the real dielectric function (R e ) and the imaginary dielectric functions (I m ) are considered.…”

“…Therefore, the role of N‐vacancy on the optical properties of the bulk GaN is worth to study in this work. Here, two key optical properties: dielectric function and optical adsorption spectra are studied 76‐79 . Figure 4 shows the calculated dielectric function diagram of the bulk GaN with the N‐vacancies.…”

Influence of Group III and IV Elements on the Hydrogen Evolution Reaction of MoS2 Disulfide

“…The environmental problems caused by the increase in fossil fuel consumption as well as the huge energy demand have invited the society to pay attention to sustainable new energy. − Hydrogen is considered a good substitute for fossil fuels due to its comprehensive sources, extremely high calorific value, nonpolluting combustion, and renewable cycle. − There are many ways to obtain hydrogen, − but hydrogen production by electrolysis of water is regarded as a reliable method due to its high purity, high efficiency, and nonpollution during the hydrogen production process. − Hydrogen production by electrolysis of water usually requires catalysts to accelerate water splitting and such catalysts are noble metals. However, due to the high price and scarcity of noble metals, the large-scale application of hydrogen production by electrolysis of water is limited. − Therefore, it is urgent to find alternative non-noble metal-based electrocatalysts.…”

First‐principles investigation of electronic and optical properties of H‐doped FeS 2

“…Molecular hydrogen (H 2 ) is regarded as the attractive energy carrier compared to the conventional fossil fuel 10‐15 . A possible method to obtain the H 2 production is the water splitting from the light or renewable energy 16‐19 . However, the main shortage of water splitting is the low H 2 production and high cost 20‐22 .…”