293 Kelvin, but at > 200 gigapascal, so not deployable. this is the kind of pressure that breaks diamond anvils. Earlier milestones: 200 Kelvin, 185 Kelvin – the field has improved by ~100 kelvin since i started paying attention in the early 90s.
Graphene superconductors exist, as of 2019:

his lab at MIT had found superconductivity in twisted bilayer graphene — a 1-atom-thick sheet of carbon crystal dropped on another one, and then rotated to leave the 2 layers slightly askew. The discovery has been the biggest surprise to hit the solid-state physics field since the 2004 Nobel Prize–winning discovery that an intact sheet of carbon atoms — graphene — could be lifted off a block of graphite with a piece of Scotch tape. And it has ignited a frenzied race among condensed-matter physicists to explore, explain and extend the MIT results, which have since been duplicated in several labs. The observation of superconductivity has created an unexpected playground for physicists. The practical goals are obvious: to illuminate a path to higher-temperature superconductivity, to inspire new types of devices that might revolutionize electronics, or perhaps even to hasten the arrival of quantum computers. But more subtly, and perhaps more important, the discovery has given scientists a relatively simple platform for exploring exotic quantum effects. “There’s an almost frustrating abundance of riches for studying novel physics in the magic-angle platform”

Also as of 2019, new states of superconductivity are being found:

Superconductivity has been shown in monolayer crystals of, for example, molybdenum disulphide or tungsten disulfide that have a thickness of just 3 atoms. ‘In both monolayers, there is a special type of superconductivity in which an internal magnetic field protects the superconducting state from external magnetic fields’. Normal superconductivity disappears when a large external magnetic field is applied, but this Ising superconductivity is strongly protected. Even in the strongest static magnetic field in Europe, which has a strength of 37 Tesla, the superconductivity in tungsten disulfide does not show any change. However, although it is great to have such strong protection, the next challenge is to find a way to control this protective effect, by applying an electric field.

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