Bi2MoO6 nanosheets assembled on LaFeO3 nanofibers with n-p type hierarchical nanostructure for enhanced HCHO sensor.

Metal oxide semiconductors (MOSs) are widely utilized in the gas-sensing field owing to their superior gas sensing performances. Herein, a hierarchical nanostructure consisting of Bi 2 MoO 6 nanosheets (NSs) assembled on LaFeO 3 nanofibers (NFs) was successfully synthesized by combining an electrospinning with a solvothermal method. The full study of the sensing performances was conducted by manufacturing commercial gas sensors based on Bi 2 MoO 6 /LaFeO 3 hierarchical nanostructure in order to showcase its potential application in gas sensing. The results show that the sensor based on Bi 2 MoO 6 /LaFeO 3 hierarchical nanostructure exhibits excellent HCHO gas sensing performances including a high response (R a /R g = 36.5), a superior selectivity and a short recovery time (τ rec = 20 s). Additionally, sensors based on Bi 2 MoO 6 NSs and LaFeO 3 NFs were also respectively fabricated to measure HCHO gas sensing performances in order to elucidate the sensing mechanism and structural superiority of the Bi 2 MoO 6 /LaFeO 3 hierarchical nanostructure. The increased capability of detecting HCHO gas can be attributed to the n-p heterostructure formed within the Bi 2 MoO 6 /LaFeO 3 hierarchical nanostructure. The findings in this work can contribute to the realization to enhance the sensing performances by designing n-p heterostructure in gas sensing material. [Display omitted] • A 1D Bi 2 MoO 6 /LaFeO 3 n-p type hierarchical nanostructure is designed and synthesized. • The novel hierarchical nanostructure displays excellent HCHO gas sensing performance. • Heterostructure and 1D nanofibrous structure jointly promote the sensing performance. • Superb sensing performances come from the synergies among designed favorable factors. • Sensing mechanism and structural merits of hierarchical nanostructure are advanced. [ABSTRACT FROM AUTHOR]