Research
At the Hobbs Lab we are interested in controlling chemistry on the nanoscale to develop materials for applications in nanoelectronics, optoelectronics and photochemistry. We use state-of-the-art nanolithography techniques to pattern materials at close to atomic length scales. We combine these patterning capabilities with advanced electron microscopy techniques to locally probe the chemical and optoelectronic properties of nanomaterials. These capabilities allow us to engineer more sustainable and energy-efficient materials for applications in nanoelectronics and chemistry.
Interactions of charged-particle beams with matter Understanding the fundamental interactions of charged-particle beams with matter is key to advancing technologies such as electron-beam, ion-beam and EUV lithography as well as analytical techniques like electron microscopy, electron energy-loss spectroscopy (EELS), cathodoluminscence (CL) and energy-dispersive x-ray (EDX) analysis. Improving our understanding of these interactions may enable us to generate patterns in materials with higher areal densities than currently possible while also allowing us to probe structural and chemical properties of materials at close to the atomic scale. As part of our research at TCD we will use advanced electron microscopy and EELS to probe lithographic materials and develop routes to ultrahigh density patterning capabilities |
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Exploiting plasmons for nanochemistry
Plasmonic nanoparticles can enhance optical fields at their surfaces, thus supporting enhanced light-matter interactions at those surfaces. When excited at resonant frequencies plasmonic nanoparticles can emit low-energy electrons, locally heat materials on the nanoscale, and enhance non-linear optical processes. This ability of plasmonic nanoparticles to convert optical energy into electronic and thermal energy on the nanoscale lends them to applications in photochemistry such as photocatalysis. At the Hobbs Lab we use electron microscopy, spectroscopy and nanolithography to study plasmon-mediated nanochemistry including (1) the decomposition of molecules at the surface of plasmonic nanoantennas; (2) the use of EELS and CL to map plasmonic excitations and their radiative decay on both isolated plasmonic nanoantennas and on hybridized systems of plasmonic nanoantennas and semiconductor nanocrystals; (3) the development of in-situ electron microscopy techniques to investigate the role of low-energy electrons in plasmon-mediated energy conversion; (4) the development of spectroscopic systems to study plasmon-driven photochemistry in-situ. The work described here could move toward investigations of plasmon-enhanced photochemistry for fuel production and chemical syntheses.
Plasmonic nanoparticles can enhance optical fields at their surfaces, thus supporting enhanced light-matter interactions at those surfaces. When excited at resonant frequencies plasmonic nanoparticles can emit low-energy electrons, locally heat materials on the nanoscale, and enhance non-linear optical processes. This ability of plasmonic nanoparticles to convert optical energy into electronic and thermal energy on the nanoscale lends them to applications in photochemistry such as photocatalysis. At the Hobbs Lab we use electron microscopy, spectroscopy and nanolithography to study plasmon-mediated nanochemistry including (1) the decomposition of molecules at the surface of plasmonic nanoantennas; (2) the use of EELS and CL to map plasmonic excitations and their radiative decay on both isolated plasmonic nanoantennas and on hybridized systems of plasmonic nanoantennas and semiconductor nanocrystals; (3) the development of in-situ electron microscopy techniques to investigate the role of low-energy electrons in plasmon-mediated energy conversion; (4) the development of spectroscopic systems to study plasmon-driven photochemistry in-situ. The work described here could move toward investigations of plasmon-enhanced photochemistry for fuel production and chemical syntheses.