Embodiments of an evaporator chamber heat flux rectifier and thermal switch are provided. Some embodiments include an evaporator layer with a first thermally conductive surface, a wicking structure for facilitating evaporation of a fluid in the vapor chamber heat flux rectifier, and a condenser layer that includes a second thermally conductive surface. Some embodiments include a middle layer, where when heat is applied to the first thermally conductive surface, the vapor chamber heat flux rectifier operates as a thermal conductor. Some embodiments that operate as a thermal switch include a non-condensable gas reservoir that is coupled to the condenser layer. The non-condensable gas reservoir may store a non-condensable gas when a threshold heat flux is applied to the evaporator layer. The non-condensable gas provides thermal insulation between the evaporator layer and the condenser layer when the threshold heat flux is not applied to the evaporator layer.