Evaluation of structural and dielectric properties of Mn2+- substituted Zn- spinel ferrite nanoparticles for gas sensor applications

•Ferrite samples possess polycrystalline nature and are effective parameter for gas sensors.•Secondary phases are showing predominant effect on dielectric behaviour.•Sensor response time is dependent on substitution of Mn2+.•The compositions of differently prepared Mn-Zn nanoferrites are showing good sensor response to LPG.•The ferrite sample Mn0.7Zn0.3Fe2O4 prepared by co-precipitation technique is more suitable for sensor fabrication.