Alternatively driven dual nanowire arrays by ZnO and CuO for selective sensing of gases

We introduce a facile synthesis and characterization of alternatively driven dual nanowire arrays with single crystalline nanostructures of ZnO and CuO as efficient gas sensing elements. Single-crystalline dual nanowires of ZnO and CuO with the average diameter of 30 nm were selectively and simultaneously grown on a single substrate via a chemical vapor deposition at 773-873 K, without the incorporation of foreign atoms. The responses of dual one-dimensional nanostructures toward the minute concentrations of hydrogen (H2), carbon monoxide (CO), and nitric dioxide (NO2) were compared at 473 K so that they clearly represented the ability to distinguish three gases unequivocally.