Physiosorption of large molecules onto surfaces has been an area of longstanding interest for the surface science group. Simple Van der Walls forces act to keep the molecules attached to the surface, while a variety of intermolecular interactions can lead to spontaneous self-assembly in the plane parallel to the surface.
Aromatic adsorption on metal surfaces plays a key role in many fields including heterogeneous catalysis, electrochemical devices, photovoltaics, corrosion protection and chemical sensing.
Chirality ("handedness") is a hot topic in surface science. In a new publication, we review the current state of knowledge about chirality in amino acid overlayers on copper surfaces, and present the findings of our own recent investigation of alanine on Cu{311} and {531}.
Industrial ammonia synthesis by the Haber-Bosch process is energy-intensive, requiring high temperatures and pressures. In the nitrogen cycle, by contrast, nitrogen fixation occurs under ambient conditions. Whereas the industrial catalyst is iron-based, the reactive centre (the 'FeMo-cofactor') in nitrogenase - the enzyme that catalyses the conversion of N2 into NH3 - is in essence an iron-sulphur nanocluster.
Pentagonal tiles pave the way towards organic electronics
New research paves the way for the nanoscale self-assembly of organic building blocks, a promising new route towards the next generation of ultrasmall electronic devices.
We have shown using STM that adsorbing NO2 molecules induces massively cooperative restructuring of Au{111} at 90 K, leading to the formation of Au nanoclusters. NO2 islands nucleate at the elbows of the clean-surface "herringbone" reconstruction pattern, and grow into the adjacent stripe domains along the fcc strips.
Molecular dynamics simulation of surface oxidation by ozone
The oxidation of surfaces is a fascinating topic, whether one's focus rests upon corrosion, catalytic activity or the resulting oxide's physical properties. An important example of the latter motivation is to be found in the oxidation of silicon, which is a key step in the fabrication of integrated circuits for electronic applications. Oxidation by exposure to "ordinary" oxygen (O2, or "dioxygen") is the standard industrial approach, but recent experimental work has suggested that exposure to ozone (O3) would produce higher-quality oxide films.
