Tungsten trioxide (WO₃) is one of most widely investigated metal oxide semiconductors as gas sensing material because of tunable sensing performance toward different analytes through composition modulation (e.g., dopants) and various morphology and crystallinity. In this work, we synthesized WO₃ nanofibers with different diameter and crystallinity through electrospinning of ammonium metatungstate hydrate (AMH)/polyvinyl pyrrolidone (PVP) nanofibers via design of experiments (DOE) followed by thermal heat treatment with the smaller average diameter being 23.0 nm. Through varying the calcination process, WO₃ nanofibers with different crystallinity were also synthesized, with the smaller average grain size being 23.0 nm. These nanofibers were then exposed to many analytes (i.e., H₂S, acetone, toluene, ethanol, ethyl benzene, NO₂, NO, and methane) under different operating temperatures (i.e., 250 to 450 °C) to investigate their effect toward sensing response. These systematic studies indicated that nanocrystalline WO₃ nanofibers with the smaller diameter (i.e., 20 nm) and/or smaller average grain sizes (i.e.,18.7 nm) exhibited best sensing performance independent of target analytes. The barrier energy was also correlated with the gas sensing performance experimentally.

三氧化钨（WO ₃）是作为气体传感材料研究最广泛的金属氧化物半导体之一，因为它通过成分调节（例如掺杂剂）以及各种形态和结晶度对不同分析物具有可调的传感性能。在这项工作中，我们通过实验设计（DOE）静电纺偏钨酸铵水合物（AMH）/聚乙烯吡咯烷酮（PVP）纳米纤维，然后进行热处理，合成了不同直径和结晶度的WO ₃纳米纤维，较小的平均直径为23.0 nm 。通过改变煅烧工艺，还合成了不同结晶度的WO ₃纳米纤维，其平均晶粒尺寸较小，为23.0 nm。然后将这些纳米纤维在不同的操作温度（即250 至 450 °C）下暴露于许多分析物（即H ₂ S、丙酮、甲苯、乙醇、乙苯、NO ₂ 、NO 和甲烷） ，以研究它们对感应响应。这些系统研究表明，具有较小直径（即20 nm）和/或较小平均晶粒尺寸（即18.7 nm）的纳米晶体WO ₃纳米纤维表现出独立于目标分析物的最佳传感性能。势垒能也与实验上的气体传感性能相关。