Metal oxide nanoparticles, such as CuO and SnO2, are outstanding systems for H2S gas sensing in air. In this work, those nanoparticles were deposited with different mixing percentages on substrates to form percolating networks of nanoparticles. Electrical electrodes were deposited on the nanoparticles’ films to investigate their gas sensing response against H2 and H2S, and their electrical characteristics. The sensor devices based on CuO–SnO2 nanoparticles revealed enhanced sensing characteristics against H2S with a sensitivity of 10 ppm. The enhanced sensing characteristics could be attributed to the formation of PN-junctions among CuO and SnO2 nanoparticles. The reasonable production cost (due to simple structure and cheap used materials), low power consumption ( ~ 1 µW for H2S at room temperature), high sensitivity, high response, and reasonable response time of the present sensors qualify them for practical implementation in portable gas sensing devices with enhanced characteristics.Open Access funding provided by the Qatar National Library. This work was supported by both Qatar National Research Fund (QNRF) under a Grant Number UREP21-035-2-013, and Qatar University fund under a Grant Number QUCG-CAS-20182019-1. The SEM/EDS measurements were accomplished in the Central Laboratories unit at Qatar University. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations