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• Several efforts have been devoted to eliminating the humidity influence of the ZnO sensor. • ZnO/MoS 2 sensor obtains a high sensitivity of 12.6 %/ppm and good sensor responses to NO 2. • The ZnO/MoS 2 sensor with four-probe shows stable responses to humidity variation at 150 °C. In this study, several strategies including coating with a hydrophobic MoS 2 layer, UV light illumination, raising temperature, alternating current (AC), and four-probe measurement have been systematically studied to overcome humidity dependence response behavior for the ZnO sensor. Catalyst-free CVD method was used to prepare pure ZnO nanorods and ZnO/MoS 2 heterostructures, and the prototypes were then fabricated on the substrates with Pt interdigital (ID) electrodes, respectively. The gas sensing properties of two sensors were systematically investigated. The ZnO/MoS 2 heterostructures-based sensor with four-probe measurement operating at 150 °C shows stable responses during a wide humidity variation range. Furthermore, the ZnO/MoS 2 sensor obtains excellent sensing performance to NO 2 with a high sensitivity of 12.6 %/ppm and high sensor responses at 150 °C and UV light illumination. Additionally, a low theoretical LoD of 6.5 ppb NO 2 is achieved for ZnO/MoS 2 heterostructures-based sensor. [Display omitted] [ABSTRACT FROM AUTHOR]