Room-temperature gas sensors have emerged as effective platforms for sensing explosive or toxic gases in ambient environment. However, room-temperature gas sensor usually suffers from extremely poor sensitivity and sluggish response/recovery characteristics due to the low reacting activity at low temperature. Herein, we present a room-temperature NO₂ sensor with greatly enhanced sensitivity and rapid response/recovery speed under ultraviolet (UV) illumination. The sensor based on In₂O₃/ZnO yolk-shell nanofibers exhibits remarkable sensitivity (R_g/R_a=6.0) to 1 ppm NO₂ and rapid response/recovery time (≤36, 68 s) under UV illumination, obviously better than negligible sensing performance and inefficient response/recovery properties in dark condition. Such excellent gas sensing properties of the In₂O₃/ZnO yolk-shell nanofibers were not only attributed to the improved photo-generated charge separation efficiency derived from the effect of heterojunction, but also related to the enhanced receptor function towards NO₂ endowed by increased reactive sites and gas adsorption. These proposed strategies will provide a reference for developing high-performance room-temperature gas sensors.

室温气体传感器已成为检测周围环境中爆炸性或有毒气体的有效平台。然而，由于低温下的低反应活性，室温气体传感器通常遭受极其差的灵敏度和缓慢的响应/恢复特性。本文中，我们介绍了一种室温NO ₂传感器，该传感器在紫外线（UV）照射下具有大大提高的灵敏度和快速的响应/恢复速度。基于In ₂ O ₃ / ZnO卵黄壳纳米纤维的传感器对1 ppm NO ₂表现出显着的灵敏度（R _g / R _a = 6.0）在紫外线照射下具有较快的响应/恢复时间（≤36、68 s），明显优于在黑暗条件下可忽略的传感性能和低效的响应/恢复特性。In ₂ O ₃ / ZnO卵黄壳纳米纤维具有如此优异的气体感测性能，不仅归因于异质结效应带来的光生电荷分离效率的提高，而且还归因于其赋予NO ₂增强的受体对NO _2的功能。增加反应位和气体吸附。这些提出的策略将为开发高性能室温气体传感器提供参考。