Diamondoid Nanostructures as sp 3 ‐Carbon‐Based Gas Sensors

International audience ; Diamondoids, sp3-hybridized nanometer-sized diamond-like hydrocarbons (nanodiamonds), difunctionalized with hydroxyl and primary phosphine oxide groups enable the assembly of the first sp3-C-based chemical sensors by vapor deposition. Both pristine nanodiamonds and palladium nanolayered composites can be used to detect toxic NO2 and NH3 gases. This carbon-based gas sensor technology allows reversible NO2 detection down to 50 ppb and NH3 detection at 25–100 ppm concentration with fast response and recovery processes at 100 °C. Reversible gas adsorption and detection is compatible with 50% humidity conditions. Semiconducting p-type sensing properties are achieved from devices based on primary phosphine-diamantanol, in which high specific area (ca. 140 m2 g–1) and channel nanoporosity derive from H-bonding.