Nanostructures Department

Department Head: Levente Tapasztó

The Nanostructures Laboratory focuses its research efforts on two-dimensional (2D) materials. Our research covers the synthesis of various 2D crystals, their atomic resolution characterization, nano-engineering, studying the electronic properties of 2D nanostructures and fabrication of proof of concept electron devices based on 2D materials and their nanostructures. Besides graphene, they study various 2D transition metal dichaclogenide single layers, as well as started the investigation of topological insulators. The research on photonic nanoarchitectures of biological origin has also been successfully continued.
Main results in 2017:

  • In the Lendület project they demonstrated that 2D MoS2-xOx crystals synthesized display a substantially increased catalytic activity for the hydrogen evolution reaction as compared to the pure 2D MoS2 phase. They also showed that the increased catalytic activity can be attributed to the single atomic oxygen substitution sites.
  • In the framework of the ERC Starting grant project they showed by theoretical modelling that the graphene transistors proposed by them based on zigzag graphene nanoribbons retain their charge and spin signal control capability even at room temperature and for large edge defect concentrations, which makes them suitable for real world applications.
  • Within the Korea-Hungary Joint Laboratory they demonstrated clear quantization steps in the conductivity of graphene nanoconstrictions defined by AFM lithography that enables the fabrication of best quality quantum point contact devices.
  • In the framework of the Graphene Flagship they performed systematic STM investigations to reveal the atomic scale defect structure of various 2D transition metal dichalcogenide crystals such as MoS2 MoSe2 WS2 and WSe2.
  • Within the EU FP7 Marie Curie project by atomic resolution STM measurements they observed interaction effects in the chaotic quantum billiard of the Dirac electrons within a graphene nanotriangle of 10 nm sides length.
  • In the OTKA project they showed that the blue colour of the butterfly wings originating from the nanoarchitectures is robust while the brown colour of chemical origin is highly sensitive to the thermal stress applied in the chrysalis stage.

web-site managed by the department: www.nanotechnology.hu