Zn doped In2O3 microtubes derived from zinc nitrate solution etched MIL-68-In for enhancing NO2 sensing property at room temperature

The reasonable design and preparation of high-performance sensing materials for detecting NO 2 is of importance to environmental conservation and public health. Herein, porous Zn-doped In 2 O 3 microtubes were fabricated by simple Zn(NO 3 ) 2 solution etching of In-MOF microrods, followed by calcination at 500 ℃ in air. The experiment has confirmed that appropriate amount of Zn introduced into In 2 O 3 can optimize electronic structure, increase the number of oxygen vacancy and efficiently improve NO 2 sensing property. In particular, compared with pristine In 2 O 3 , Zn-In 2 O 3 sensor exhibits excellent selectivity, high response, fast recovery speed (32 s) and lower limit of detection (LOD, 20 ppb) at room temperature. Meanwhile, the Zn-In 2 O 3 sensor also presents outstanding reproducibility, stability and humidity resistance. The excellent gas sensing property is traced to the construction of the hollow and porous structure and the synergistic optimization of Zn doping. This endeavor yields a simple strategy for the design of high-property gas sensing materials.