Laser synthesis of clean mesocrystal of cupric oxide for efficient gas sensing†
Mesocrystals are known to be unusual materials derived from the self-assembly of nanoparticles. However, their advantages arising from their unique structure have not been fully exploited to date owing to hindrance by a secondary phase. Herein, we employ a pulsed laser to synthesize mesocrystalline cupric oxide (CuO) with pure phase and clean surface. A gas sensor based on a CuO mesocrystal exhibits the highest sensitivity, the fastest response, and the best selectivity ever reported towards ethanol. Our study elucidates the inherent characteristics of mesocrystals and clears doubts regarding their practicability.