Introduction of galvanic replacement reactions at the nanoscale to undergraduate students: Synthesis of hollow metal nanostructures
by Chen, Jingyi
The rapid academic and industrial development of advanced materials at the nanoscale has led to its implementation in lab. teaching for undergraduate-level Chem. and Engineering students. In this work, a lab. expt. will be presented that introduces the galvanic replacement reaction for synthesis of hollow metal nanoparticles and investigates the optical properties of these nanoparticles. The galvanic replacement provides a robust means to synthesize hollow metal structures for their use in many areas ranging from biomedical to catalytic applications. This expt. connects the concept of replacement reaction introduced in general chem. to the synthesis method of advanced materials for practical applications which encourages students into the materials research. Changes of localized surface plasmon resonance from solid to hollow nanoparticles are monitored by UV-vis spectroscopy while corresponding morphol. changes are validated by transmission electron microscopy. The optical properties are further investigated by the use of a laser pointer, laser irradn., and surface-enhanced Raman spectroscopy. By performing these expts., students gain practical knowledge for the synthesis of hollow metal nanoparticles and the underlying structure-dependent optical properties. The experience of implementation of this expt. as a module for Phys. Chem. Lab. and a multidisciplinary Nanotechnol. Lab. courses will be discussed.