Beilstein Arch. 2024, 202413. https://doi.org/10.3762/bxiv.2024.13.v1
Published 11 Mar 2024
The thermal response of gold and platinum spherical nanoparticles (NPs) upon cooling is studied through atomistic molecular dynamics simulations. The goal is to identify the morphological transformations occurring at the nanomaterials as well as to quantify their dependence on temperature, chemistry and NP size. For diameters smaller than 3 nm, the transition temperature from a melt / amorphous to a highly crystalline state varies considerably with NP size. For larger diameters, the transition temperature is almost temperature-independent, yet it differs considerably from the transition temperature of the respective bulk materials. The platinum NPs possess a higher level of crystallinity than the gold counterparts under the same conditions due to the stronger cohesive forces which drive the crystallization process. This observation is also supported by the simulated X-ray powder diffraction patterns of the nanomaterials. The larger NPs have a multifaceted crystal surface and their shape remains almost constant regardless of temperature variations. The smaller NPs have a smoother and more spherical surface while their shape varies greatly with temperature. By studying the variation of nano-descriptors commonly employed in QSAR models, a qualitative picture of the NPs toxicity and reactivity emerges: small / platinum NPs are likely more toxic than their large / gold counterparts. Due to the small size of the NPs considered, the observed structural modifications are challenging to be studied by experimental techniques. The present approach can be readily employed to study other metallic and metal oxide nanomaterials.
Keywords: nanoparticle; toxicity; gold; platinum; molecular dynamics; size; morphological transformation; phase change
| Format: DOCX | Size: 487.9 KB | Download |
When a peer-reviewed version of this preprint is available, this information will be updated in the information box above. If no peer-reviewed version is available, please cite this preprint using the following information:
Voyiatzis, E.; Valsami-Jones, E.; Afantitis, A. Beilstein Arch. 2024, 202413. doi:10.3762/bxiv.2024.13.v1
Citation data can be downloaded as file using the "Download" button or used for copy/paste from the text window below.
Citation data in RIS format can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and
Zotero.
© 2024 Voyiatzis et al.; licensee Beilstein-Institut.
This is an open access work licensed under the terms of the Beilstein-Institut Open Access License Agreement (https://www.beilstein-archives.org/xiv/terms), which is identical to the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0). The reuse of material under this license requires that the author(s), source and license are credited. Third-party material in this work could be subject to other licenses (typically indicated in the credit line), and in this case, users are required to obtain permission from the license holder to reuse the material.
