UV-initiated formation of noble metal nanoparticles on zinc oxide quantum dots

Full text: Quantum dots (nanosized semiconductor particles) are a relatively new phenomenon. They exhibit unusual properties as a result of spatial electron confinement within the particles, including an increased band gap energy and blue-shifted fluorescence. Quantum dots and nanoparticles have attracted a lot of academic and industrial interest because of their special properties, including small size and potential as catalysts, 'tunable' fluorescence, and potential use in biomedical applications. Still, there are many properties of quantum dots that need further investigation if they are to be fully utilised. The interaction between nanosized noble metal colloids and zinc oxide quantum dots (Q-ZnO) under UV-irradiation provides valuable information about the electronic structure of Q-ZnO. In a sample containing Q-ZnO and Pt6+, Au+ or Ag+, electrons from excited Q-ZnO were transferred to the metal ions, and consequently, metal particles were reduced onto the Q-ZnO particles. The processes that occur can be followed spectroscopically. The results will be discussed during the presentation. A Transmission Electron Microscope image of a 3nm zinc oxide quantum dot, with lattice planes clearly visible is presented