Thermo-optic switching properties of paraffin-wax hosting carbon fillers

•Thermo- optical parameters of paraffin wax are investigated using light transmission under electric heating of paraffin wax, Moreover embedding the carbon fillers to paraffin wax matrix in order to enhance the thermo- optical parameters.•Carbon fillers promote decreasing of switching and saturation times, paraffin wax-graphene composite samples cause up to 54% reduction in thermo optical switching parameters when increasing their concentration.•Thermal stability of paraffin wax was examined after five thermal cycles; insignificant change in DSC and TOS parameters are confirmed.•Heat transfer rate of the paraffin composites were studied which confirm that graphite and graphene accelerate melting and solidification of paraffin wax.•These experiments showed a route for paraffin wax hosting carbon fillers as thermo optical sensing materials to be used in TOS device applications.