Confined volume plasmon spatial distribution by low-loss EELS on self-assemble bismuth nanoparticles

Abstract

Bismuth nanoparticles have been synthesized via solvothermal reaction with high yield, as a function of reaction parameters: pH, temperature and precursor concentration (sodium hypophosphite). Morphology characterization of the synthesized products by scanning electron microscopy shows nanobelts formation is favored under acidic pH (2 and 4) conditions. Structural characterization by transmission electron microscopy shows that nanobelts are self-assembled rhombohedral metallic bismuth nanoparticles (5.54 ± 1.87 nm (pH4)) and no other morphology was found, therefore a mechanism for self-assembled nanobismuth is proposed. Study and characterization of bulk plasmon blue-shift on bismuth nanoparticles due to quantum confinement effects was observed by mapping the volume plasmon energy as a function of position by electron energy loss spectroscopy. It shows that self-assembled nanobismuth into nanobelts is a practical structure for the evaluation of bismuth optoelectronic properties in the nano-scale regimen, given that no structural fluctuations due to irradiation of high energy electrons coming from the electron microscope were observed during the mapping of volume plasmon energies on individual bismuth nanoparticles. Association of size, shape and volume plasmon energy on nanobismuth will deliver clearer insight into how the characteristic materials can be tailored for practical applications.