The influence of Ammonia on the electrical properties of detonation nanodiamond

Detonation nanodiamonds (DNDs) are an interesting class of materials for sensing applications, but little is currently understood about their electrical properties. Here, aggregated DNDs are explored with impedance spectroscopy and are found to offer near-to-ideal dielectric characteristics, which is intriguing given their nanostructure. When exposed to ammonia, two highly conductive pathways emerge through the material; these appear to be associated with grain boundary and grain interior processes, the latter potentially due to surface transfer doping. This process is reversible given modest temperature increases suggesting DNDs may offer a solid state electrical platform for ammonia sensing applications