Comparison of gas sensing properties based on hollow and porous alpha-Fe2O3 nanotubes

Hollow and porous alpha-Fe2O3 nanotubes were successfully synthesized by single nozzle electrospinning method followed by annealing treatment. The crystal structures and morphologies of the as-prepared materials were characterized by X-ray diffraction and scanning electron microscopy, respectively. The as-prepared materials were applied to construct gas sensor devices which gas sensing properties were further investigated. The obtained results revealed that porous alpha-Fe2O3 nanotube gas sensors exhibit a markedly enhanced gas sensing performance compared with hollow alpha-Fe2O3 nanotube gas sensors, which was about three times higher to 100 ppm acetone at 240 A degrees C. Interestingly, hollow and porous alpha-Fe2O3 nanotube gas sensors both showed fast response-recovery time and good selectivity, but the porous ones possessed the shorter recovery time. The improved properties could be attributed to the unique morphology of porous nanotubes. Thus, further improvement of performance in metal-oxide-semiconductors materials could be realized by preparation the unique porous structures of nanotubes. Moreover, it is expected that porous metal-oxide-semiconductors nanotubes could be further design as promising candidates for gas sensing materials.