为了检测建筑物室内甲醛，用ZnO纳米线作为监测甲醛的目标物。以氯化锌(ZnCl2)和柠檬酸钠(C6H5Na3O7)为原料，使用水热法合成ZnO纳米线，利用X射线衍射仪(XRD)、扫描电镜(SEM)和X射线能谱仪(EDS)对制备出的ZnO纳米线的晶体结构和微观形貌进行表征。结构表征结果表明，所制备出的ZnO纳米线结晶良好、纯度较高，平均直径为(39±10) nm，其长度约为400 nm，且分散良好。将所制备的ZnO纳米线涂覆在陶瓷管上，组装成气敏元件并对其进行系统的气敏特性研究。气敏检测结果表明，基于ZnO纳米线的气体传感器对HCHO气体具有优异的气敏性能。该传感器在125 ℃时对50×10-6的HCHO气体获得最大灵敏度15.2，同时展现出了优良的稳定性、重现性以及选择性。

In order to detect the formaldehyde content in building interiors, ZnO nanowire was used as the target for monitoring formaldehyde. ZnO nanowires were synthesized by hydrothermal method using zinc chloride (ZnCl2) and sodium citrate (C6H5Na3O7) as raw materials. The crystal structure and micromorphology of the prepared ZnO nanowires were analyzed by XRD, SEM and EDS. Structural characterization results show that the prepared ZnO nanowires have good crystallinity and high purity, with an average diameter of (39±10) nm, a length of about 400 nm, and good dispersion. As-prepared ZnO nanowires were brushed-coated on a ceramic tube, assembling into a gas sensor, and investigated systematic gas-sensing properties of sensor. The gas sensing test results show that the ZnO nanowire-based gas sensor has excellent gas-sensitivity properties to HCHO gas, and obtain a maximum sensitivity of 15.2 to 50×10-6 HCHO gas at the optimal working temperature of 125 ℃. In addition, it has good stability, reproducibility and selectivity.