Highly sensitive toluene sensor based on porous core-shell-structured In2O3-ZnO nanofibers under UV irradiation at room temperature

Porous core-shell-structured In2O3-ZnO nanofibers (NFs) were synthesized using two-step method. The porous and core-shell structure of the In2O3-ZnO NFs was confirmed using field emission scanning electron microscopy and field emission transmission electron microscopy. Gas sensing experiments showed that the In2O3-ZnO NFs exhibited a response of 34.7-100 ppm of toluene gas at room temperature (RT), which was 5.5- and 6.4-fold higher than that of the pure ZnO NFs and pure In2O3 NFs, respectively. The In2O3-ZnO NFs sensor also demonstrated fast response, excellent selectivity, and long-term stability at RT. The enhanced sensing properties for toluene gas were attributed to the larger specific surface area, higher concentration of chemisorbed oxygen species, and core-shell heterostructure of the In2O3-ZnO NFs. The authors anticipate that this study will facilitate the development of future gas sensors for the detection of toluene gas at RT.

Automated summary

In this study, porous core-shell-structured In2O3-ZnO nanofibers were synthesized and their excellent sensing properties for toluene gas were confirmed. The sensor exhibited fast response, excellent selectivity, and long-term stability at room temperature.