XENON1T is the most sensitive WIMP-like dark matter detector in the world, with sensitivity reaching the scale of 10^-47 cm^2 Spin Independent cross section with a 30 GeV/c^2 dark matter particle. This achievement is a result not only the increase of target mass but also of great effort to reduce background. The next generation detector, XENONnT, is now under construction. It is designed to increase the mass of the detector to 8 tons and to reduce background another order of magnitude. One background effect which the collaboration is trying  to reduce is the single electron emission.

In this talk I will describe the challenges undertaken by the XENONnT upgrade. In doing so, I will briefly describe the detector’s designed physics reach, and, in particular, the novel liquid xenon purification system designed to reduce the single electron background and add to the reduction of radon decays backgrounds.