Research Activities

High resolution imaging (SEM, TEM, Z-contrast STEM)

SEM image of a sample of multiwalled carbon nanotubes (MWCNT)

High resolution imaging is obtained in all our microscopes with a wide variety of detection systems. The Magellan 400L extreme resolution (XHR) SEM offers subnanometer resolution over the full 1 kV to 30 kV electron energy range, providing surface specific information otherwise unattainable. The Quanta 650 FEG environmental SEM (ESEM) is suited to study specimens at low vacuum and extended vacuum (environmental) conditions, with a resolution of 1.4 nm. The Tecnai G2 F20 HRTEM has an S-Twin objective lens which provides a resolution of 0.24 nm in TEM mode (further extended to 0.16 nm using TrueImage focus series reconstruction software) and 0.19 nm resolution in HAADF STEM mode (Z-contrast).

Chemical analysis at the nanoscale (EDS, EELS, EFTEM)

EDX spectrum of a sample of ZnO nanoparticles. 

Point analysis, line profiles and chemical maps are readily available in the Quanta 650 FEG and the Tecnai G2 F20. The Quanta 650 FEG is coupled to an Inca 250 SSD XMax20 detector with a resolution of 129 eV (at Mn Kα) for EDS analysis. On the other hand, the Tecnai G2 F20 is a powerful analytical tool thanks to its EDAX detector for EDS studies and the new generation GIF QuantumSE imaging filter for high performance EELS and energy filtered imaging. Spectrum imaging and profiling capabilities are available in STEM mode for both EDS and EELS.

Structural characterization by electron diffraction

Electron Diffraction

Study of crystalline specimens by electron diffraction is possible in the Tecnai G2 F20. The electron diffraction pattern formed at the back focal plane of the microscope can be projected to the viewing device, providing information about the crystal lattice (shape, orientation and spacing of the lattice planes).

Electron tomography

Tomographic reconstruction of a Zn(bix) metal-organic sphere with encapsulated gold nanoparticles. Sample provided by Marta Rubio, Dr. Inhar Imaz and Dr. Daniel Maspoch. Data acquired by Dr. Juan Carlos Hernández-Garrido and Prof. Paul A. Midgley (University of Cambridge)

3D information of nanomaterials is obtained by TEM and HAADF STEM electron tomography in the Tecnai G2 F20, using a high-tilt tomography holder (up to 80º tilt) and the specific software for data acquisition, reconstruction and visualisation.

Dynamic in-situ experiments

In-situ microscopy for observing dynamic processes at the nanoscale is carried out in the Quanta 650 FEG ESEM, with control over temperature and humidity conditions provided by a heating stage which can get up to 1000ºC and a Peltier cell which allows reaching humidity up to 100%.