Enhanced chemiresistive sensing performance of well-defined porous CuO-doped ZnO nanobelts toward VOCs

thermal oxidation, a uniform and stable sensing film consisting of porous CuO-doped nanobelts was fabricated. Compared with pristine porous ZnO nanobelts, the as-prepared porous CuO-doped nanobelts with p-type CuO|n-type ZnO heterojunctions exhibited better sensing performance toward volatile organic compounds (VOCs). Especially for 3 at% CuO-doped porous ZnO nanobelts, the relative responses toward 100 ppm of ethanol, acetone and formaldehyde were greatly enhanced more than two, four and ten times, respectively. Due to the porous structure, they also displayed a fast response/recovery time. Finally, this enhanced sensing mechanism was discussed for porous CuO-doped ZnO nanobelts.