Determination of impurities in graphite using synchrotron radiation based X-ray fluorescence spectrometry.
Determination of impurities namely Ca, Mn, Fe, Ni, Zn, Sr and Pb in graphite by energy dispersive X-ray fluorescence spectrometry is described using microfocused synchrotron radiation. The internal standard and standard addition methodologies were adopted for quantification and the results were compared with tube-based X-ray fluorescence spectrometry. Analysis of the results by the F and t-tests revealed their statistical equivalence. Synchrotron measurements improved the detection limits by an order of magnitude compared to the tube based technique. Cr and Zr, which were below the quantification limit in tube based technique, were also quantified by synchrotron based technique.
Graphene-derived materials as oxygen reduction catalysts in alkaline conditions for energy applications
Graphene is a relatively new carbon material increasingly finding technological applications due to its unique physical and engineering properties. Here, its application as catalyst for the oxygen reduction reaction (ORR) in alkaline media is investigated. 
First, the role of graphene-related materials (including multi-walled carbon nanotubes) as catalyst supports is compared to the widely used carbon black, finding that the ORR follows a mixed behaviour between the direct 4-electron pathway and the indirect 2-step mechanism on graphene-supported platinum catalysts. 
Further, different combinations of boron, nitrogen, phosphorus and sulphur metal-free doped-graphene catalysts have been systematically synthesised and evaluated, finding that dual-doped graphene catalysts yield the best ORR performance. Specifically, phosphorus and nitrogen dual-doped graphene (PN-Gr) demonstrates the highest catalytic activity, with 3.5 electrons transferred during the ORR. 
Doped-graphene/perovskite oxide hybrid catalysts have been also tested, yielding PN-Gr/La0.8Sr0.2MnO3 the best ORR activity in terms of measured current density, achieving a value that is 85% of that reported for a commercial Pt/C catalyst. Moreover, SN-Gr/La0.8Sr0.2MnO3 produces the lowest amount of peroxide formation with only 10%. 
These results confirm the graphene-derived catalysts as promising alternatives to the current platinum-based catalysts, and could enable the important issues related to its practical application to be overcome.
The determination of barium, platinum and ruthenium in experimental catalysts by neutron activation analysis
The determination of platinum and ruthenium in the presence of barium by instrumental neutron activation analysis is hampered by interference from barium isotopes. This difficulty is surmounted by utilizing gold and rhodium isotopes produced from the β-decay of platinum and ruthenium isotopes.