Electronically tunable near-field radiative heat transfer between doped silicon and graphene-covered silicon dioxide

•The near-field radiative thermal switch made of the n-type doped silicon and graphene-covered silicon dioxide plates is comprehensively investigated.•The modulation is due to the surface mode of the graphene-covered silicon dioxide, which is significantly affected by the graphene chemical potential value via applying the external voltage bias.•The D-Si doping concentration and the breakdown voltage of dielectric materials also can significantly affect the performance of the near-field radiative thermal switch.•The thermal switching factor of the near-field radiative thermal switch can be improved to 93.5% across a 10 nm vacuum gap by altering the graphene chemical potential value from 0 to 1 eV.