Abstract
Abstract
This article explored the influence of lithium on cobalt-doped ZnO thin films fabricated via the sol–gel spin coating technique for NO2 gas sensing applications. The abundance of oxygen vacancies in ZnO can be proven by scanning electron microscopy, four-probe Hall measurements, photoluminescence spectroscopy, UV-visible spectroscopy, and x-ray photoelectron spectroscopy. The presence of lithium plays a crucial role in generating more oxygen vacancies in Co-doped ZnO was discussed. Among the fabricated samples, (Li-Co) co-doped ZnO exhibits better sensitivity (2940.17%), selectivity, repeatability, and stability (after 90 days) toward 75 ppm NO2 gas.