Synthesis and H₂S sensing performance of MoO₃/Fe₂(MoO₄)₃ yolk/shell nanostructures

Abstract

A facile method was developed to fabricate MoO3/Fe2(MoO4)3 yolk/shell nanostructures with small pores, exhibiting good H2S gas sensing performance including high sensor response, short recovery and response times, and good selectivity and stability.

Advances in the designs and mechanisms of MoO3 nanostructures for gas sensors: a holistic review

“…In particular, these 3-D HNS owing to their large SSA and minimized interparticle agglomerations, provides an easier gas molecule diffusion and faster charge propagation on the material's surface, thus resulting in high sensitivity and a faster response sensing speed 10,169 . Till now, a variety of 3-D MoO3 nanostructures, including nano/micro-flower 83,84,[166][167][168]170 , hierarchical 53,73,[130][131][132][133][134][135] , nanoarrays [177][178][179] , hollows spheres 180,181 , core-shell [182][183][184] , microcage 185 , nanopompon 186 , and microbox 187 have been designed and used in the gas sensing applications (Table 3).…”

Porous MoO3/SnO2 Nanoflakes with n–n Junctions for Sensing H2S

“…The sensors were assembled according to our previous method. , Schematic diagram of device is described in Figure S1. Figure S1a illustrates the configuration of sensor.…”

“…Hydrogen sulfide (H 2 S) is a colorless, toxic, flammable, and rotten-egg-smelling gas, which is very harmful to human beings’ bodies even at low concentration. − Usually, H 2 S is produced in coal mines, petroleum refining, natural gas exploration, sewage treatments, and automobile vehicle exhaust. − According to security criterion proclaimed by American Conference of Government Industrial Hygienists, threshold limit value of H 2 S was stipulated as 10 ppm . Thus, developing efficient H 2 S gas sensor with high sensitivity, excellent selectivity, and rapid response is urgent.…”

Self-assembly gridding α-MoO3 nanobelts for highly toxic H2S gas sensors

“…However, the response and recovery times of the above-mentioned H2S gas sensors were as long as 2 min ~ 8 min, suggesting it difficult to push forward the practical applications. To achieve this, some H2S gas sensors based on ZnO nanorods [7,8], NiO porous nanowall arrays [9,10], different CuO nanostructures [11][12][13][14][15][16], In2O3 nanoparticles [17], metals ions doping WO3 and MoO3 nanowires [18][19][20][21][22][23][24] were designed to improve the response/recovery times for detecting highly toxic H2S gas. However, there are still many challenges toward the widely commercial applications, such as the bad selectivity and stability.…”