Journal article

Enhanced electrochemical capacitance of nitrogen-doped ultrananocrystalline diamond through oxygen treatment

Samira Falahatdoost, Andre Chambers, Alastair Stacey, Hassan N Al Hashem, Athavan Nadarajah, Steven Prawer, Arman Ahnood



The electrochemical capacitance of nitrogen-doped ultrananocrystalline diamond (N-UNCD) can be dramatically increased by treating the surface with an RF-oxygen plasma. Such treated surfaces display excellent properties for use as electrodes in neural stimulation and recording. In the present work, we elucidate the origins of this phenomenon by investigating the effects of different methods of oxygen termination. We found that the increase in electrochemical capacitance is dependent on the details of the method used for oxygen termination. Whilst N-UNCD subjected to UV/ozone treatment, oxygen plasma treatment, and furnace annealing in oxygen gas all displayed increased surface capacitance, th..

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Awarded by Australian Research Council (ARC)

Funding Acknowledgements

AN and AS are supported by the Australian Research Council (ARC) via Linkage Grant LP160101515 and fellowship (DE190100336), respectively. AC is supported by an Australian Government Research Training Program (RTP) Scholarship. This research was undertaken on the Soft X-ray Spectroscopy beamline at the Australian Synchrotron, part of ANSTO. The authors wish to acknowledge the Ian Holmes Imaging Centre at the Bio21 Institute, University of Melbourne for assistance with electron microscopy. The authors also acknowledge the facilities, as well as the scientific and technical assistance of the Australian Microscopy & Microanalysis Research Facility at the RMIT University.