Design of nanoneedles-studded nanosheets on cactus-like Mo-WO3 nanoarchitecture for boosted NO2 sensing performance.

[Display omitted] • Cactus-like Mo-WO 3 assembled of 1D nanoneedles and 2D nanosheets was prepared. • The nanoneedles were vertically studding in the nanosheets increasing exposed sites. • Oxygen vacancies generated and the adsorption sites were activated after Mo doping. • The optimized 2%Mo-WO 3 exhibited enhanced sensitivity and recovery time to NO 2. We reported the design of cactus-like Mo-WO 3 nanoarchitecture assembled of 1D nanoneedles and 2D nanosheets for achieving a highly improved NO 2 sensing performance. The nanoneedles were vertically studding between the nanosheets forming a cactus-like WO 3 nanoarchitecture, leading to highly exposed absorption sites. Mo was introduced in the WO 3 nanoarchitecture to introduce oxygen vacancy, resulting in highly activated sites. The resultant 2%Mo-WO 3 delivered the sensitivity (Rg/Ra) of 285 to 10 ppm NO 2 , which was nearly three-times higher than that of pristine WO 3. The recovery time was only 24 s, which was greatly decreased, compared with 172 s of pristine WO 3. [ABSTRACT FROM AUTHOR]