1. A data center cooling system, comprising:an outer container that defines a first volume;
an inner container that defines a second volume and is positioned within the first volume, the inner container comprising an air outlet that comprises an airflow path between the first and second volumes;
a liquid seal to fluidly isolate a liquid phase of a non-conductive coolant that fills at least a portion of the first and second volumes from an ambient environment;
at least one server tray assembly comprising:a plurality of electronic heat-generating devices immersed in the liquid phase of the non-conductive coolant; and
an immersion cooling system mounted to and in conductive thermal contact with one or more of the plurality of electronic heat-generating devices, the immersion cooling system comprising: a working fluid in thermal communication with the one or more electronic heat-generating devices and the non-conductive coolant, a vapor chamber mounted to and in conductive thermal contact with the one or more electronic heat-generating devices, and one or more heat transfer devices positioned in thermal contact with the working fluid within an inner volume of the vapor chamber and in thermal contact with a liquid phase of the non-conductive coolant.