Designed\nSynthesis of In₂O₃ Beads@TiO₂–In₂O₃ Composite Nanofibers for High Performance NO₂ Sensor at Room Temperature

Abstract

Porous\nsingle crystal In₂O₃ beads@TiO₂–In₂O₃ composite nanofibers (TINFs) have been prepared\nvia a facile electrospinning method. The beads were\nformed because of the existence of hemimicelles in pecursor solution.\nThe formation of hemimicelles was attributed to the synergy of tetrabutyl\ntitanate (TBT) and polyvinylpyrrolidone (PVP). Abundant In³⁺ ions were drawn toward the ketonic oxygen of PVP resulting in In³⁺ ions aggregation. Compared with pristine In₂O₃ nanofibers (INFs), the as-prepared TINFs exhibited excellent\nproperties for sensing NO₂ gas at room temperature (25\n°C). The enhanced sensing property was due to much absorbed oxygen\nand Schottky junctions between the porous single crystal In₂O₃ beads and the Au electrode of the sensor. The strategy\nfor combining the unique In₂O₃ beads@TiO₂–In₂O₃ nanofibers structure which\npossessed superior conductivity and sufficient electrons with the\naddition of TiO₂ offered an innovation to enhance the gas\nsensing performance.