Hybrid Co₃O₄/SnO₂ Core–Shell Nanospheres as Real-Time Rapid-Response Sensors for Ammonia Gas

Abstract

Novel hybrid Co3O4/SnO2 core-shell nanospheres have been effectively realized by a one-step hydrothermal, template-free preparation method. Our strategy involves a simple fabrication scheme that entails the coating of natural cross-link agents followed by electrostatic interaction between the positive charges of Sn and Co ions and the negative charge of glutamic acid. The core-shell architecture enables novel flexibility of gas sensor surfaces compared to commonly used bulk materials. The highly efficient charge transfer and unique structure are key to ensuring the availability of high response and rapid-response speed. It demonstrates how hybrid core-shell nanospheres can be used as an advance function material to fabricate electrical sensing devices that may be useful as gas sensors.

Hydrothermal Synthesis of Co3O4/ZnO Hybrid Nanoparticles for Triethylamine Detection

“…The typical n-type semiconductor ZnO is considered to be an extremely beneficial gas-sensing material by reason of good chemical stability, non-toxicity, high surface-to-volume ratio, suitable doping, and low cost [9,10,11]. It is worth noting that the fabrication of heterostructure composite sensors can enhance gas-sensing performances and significantly improve the low sensitivity and poor selectivity of pure ZnO materials [12,13,14]. Kim et al [15] reported the CuO-ZnO heterostructure nanorods sensor to enhance H 2 S gas response and repeatability over pure ZnO.…”

A highly sensitive gas sensor employing biomorphic SnO2with multi-level tubes/pores structure: bio-templated from waste of flax

“…9). 6,26 In this work, the optimal operating temperature of MLTPS was 130 C. At low operating temperatures (<200 C), 34,45 the chemisorbed oxygen ion process can be expressed as follows: 26…”

Metal Oxide Based Heterojunctions for Gas Sensors: A Review

“…The SnO 2 /SiO 2 heterojunctions were synthesised via a facile method of a magnetron sputtering process and exhibited promising H 2 sensing performance at room temperature [51]. Hybrid Co 3 O 4 /SnO 2 core-shell nanospheres prepared with a onestep hydrothermal method demonstrated a measured response of 13.6 to 100 ppm NH 3 at 200 • C, a value two times higher than that of the solid nanospheres [52]. CeO 2 -decorated ZnO nanosheets were prepared by a hydrothermal process in combination with the wet impregnation method, exhibited an enhanced sensor response of 90 to 100 ppm ethanol at 310 • C [53].…”