Nanomaterials for energy
Nanomaterials play a large role in the development of new technologies for energy storage and conservation, ranging from solar cells, batteries to catalysis. In other fields, such as sensors, ‘smart’ windows and new electronics, nanomaterials are known to be equally important.  The properties of materials are highly dependent on both the atomic arrangement and the nanostructure of the material, and it is therefore crucial to be able to precisely control particle characteristics during synthesis.
We use new methods in nanomaterial synthesis, combining traditional solid state chemistry with new techniques from organic and inorganic chemistry  to form novel nanomaterials with tailormade characteristics and properties. We are particularly interested in ultrasmall nanoparticles and clusters with dimensions below 5 nm, where the atomic structure and material properties are fundamentally different from bulk.

X-ray and neutron scattering for nanomaterial characterization
The development of materials for sustainable energy such as catalysis, solar cells and batteries builds on an intricate understanding of the relation between material structure and properties. Only by knowing the atomic arrangement can the mechanisms responsible for material properties be elucidated and new materials developed.
We use X-ray and neutron scattering to study the atomic structure of materials. By combining traditional crystallographic methods with new total scattering techniques, we are able to elucidate the structures even in ultrasmall nanoparticles, where the atomic arrangement differ significantly from the bulk.

For an example of our research in the use of X-ray total scattering for nanostructure analysis, see. e.g.:

Lindahl Christiansen et al: Size Induced Structural Changes in Molybdenum Oxide Nanoparticles, ACS Nano, 13, 8725-8735, 2019

Jensen et al: Polymorphism in magic-sized Au144(SR)60 nanoclusters 
Nature Communications, 7, 11859, 2016


Understanding the formation of nanoparticles – watching materials form with X-rays
X-ray total scattering allows strutural information to be obtained from both amorphous and crystalline samples; liquids as well as solids. By using X-ray total scattering in situ during nanoaparticle formation i.e. by taking X-ray data while the synthesis takes place, we are able to follow the structural transformation that takes place as the atoms arrange to form ordered nanoparticles. This gives us new insight into reaction mechanisms, taking us one step closer to ‘materials by design’.

For examples of in situ X-ray total scattering, see e.g.:

Juelsholt et al: Mechanisms for Tungsten Oxide Nanoparticle Formation in Solvothermal Synthesis: From Polyoxometalates to Crystalline Materials. J. Phys. Chem. C, 123, 5110-5119, 2019

Jensen et al: Revealing the mechanisms behind SnO2 nanoparticle formation and growth during hydrothermal synthesis: an in situ total scattering study.
J. Amer. Chem. Soc, 134 (15), 6785-6792, 2012

Jensen et al: Mechanisms for iron oxide formation under hydrothermal conditions: an in situ total scattering study.
ACS Nano, 8 (10), 10704-10714, 2014

Jensen et al: In situ studies of solvothermal synthesis of energy materials.
ChemSusChem, 7 (6), 1594-1611, 2014