High Ultraviolet Absorption in Colloidal Gallium Nanoparticles Prepared from Thermal Evaporation

Nanomaterials

Encarnación Lorenzo¹  Iria Bravo¹  Jose Luis Pau²  Sergio Catalan-Gomez²  Luis Vázquez³  Flavio Nucciarelli⁴ 

[1] Departamento de Química Analítica y Análisis Instrumental, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain;Grupo de Electrónica y Semiconductores, Departamento de Física Aplicada, Universida Autónoma de Madrid, 28049 Madrid, Spain;Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, CSIC, 28049 Madrid, Spain;Physics Department, Lancaster University, Lancaster LA1 4YB, UK;

关键词: gallium;    nanoparticle;    colloid;    AZO;    tetrahydrofuran;    thermal evaporation;    DDA simulation;   

DOI  :  10.3390/nano7070172

来源: DOAJ

【 摘 要 】

New methods for the production of colloidal Ga nanoparticles (GaNPs) are introduced based on the evaporation of gallium on expendable aluminum zinc oxide (AZO) layer. The nanoparticles can be prepared in aqueous or organic solvents such as tetrahydrofuran in order to be used in different sensing applications. The particles had a quasi mono-modal distribution with diameters ranging from 10 nm to 80 nm, and their aggregation status depended on the solvent nature. Compared to common chemical synthesis, our method assures higher yield with the possibility of tailoring particles size by adjusting the deposition time. The GaNPs have been studied by spectrophotometry to obtain the absorption spectra. The colloidal solutions exhibit strong plasmonic absorption in the ultra violet (UV) region around 280 nm, whose width and intensity mainly depend on the nanoparticles dimensions and their aggregation state. With regard to the colloidal GaNPs flocculate behavior, the water solvent case has been investigated for different pH values, showing UV-visible absorption because of the formation of NPs clusters. Using discrete dipole approximation (DDA) method simulations, a close connection between the UV absorption and NPs with a diameter smaller than ~40 nm was observed.

【 授权许可】

Unknown