Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

In Material Science (powder) diffraction methods are a common sample characterisation tool. Beside the laboratory sources synchrotron radiation offers the advantages of high brilliance and tuneable wavelength. As an example for high resolution diffraction the localisation of incorporated guest molecule in zeolites faujasite by crystal structure refinement will be presented.
Heavy load goniometer allows also experiments with high sophisticated sample environments to perform in-situ investigations. Hereby solid state reactions can be monitored or catalyst characterized. Carbon nano tubes (CNT) are synthesized by chemical vapour deposition and the use of iron nano particles. The catalyst processing and CNT synthesis was observed by XRD and the catalytic active species determinated.
By the use of hard X-rays absorption effects are minimized and more complex system like a secondary lithium ion battery can be investigated. Hereby the diffraction pattern of the system in operation can be collected. The charge-discharge behaviour of lithium manganese oxide will be discussed.
In general in-situ investigations have the advantage to monitor different processes directly and being more time efficient. Misleading results of ex-situ measurements by metastable phases, subsequent reactions or aging of the material are avoided.