German physicists from Leipzig University have discovered that ordinary graphite, after a simple treatment with water, can exhibit signs of superconductivity at temperatures above 100 °C. This discovery, described in a paper accepted for publication in the journal Advanced Materials, still requires confirmation by other groups, but it already forces us to reconsider conventional ideas about materials.
The team of Professor Pablo Esquenazi worked with graphite flakes — the very material used in pencil leads. The scientists placed 100 milligrams of powder in 20 milliliters of distilled water, stirred the mixture for 23 hours, then filtered it and dried it at 100 °C. After such treatment, the material exhibited unusual magnetic properties reminiscent of the behavior of high-temperature superconductors discovered back in the 1980s.
Superconductivity means that an electric current flows without resistance and without energy losses. In ordinary wires, a significant portion of the electricity turns into heat, so grids require complex cooling systems and enormous costs. If it were possible to create a material that works at room temperature or even higher, energy transmission would become far more efficient, and equipment would become simpler and cheaper.
The researchers observed that the magnetization of the samples persisted after the external field was switched off, and the graphs of its dependence on temperature and field resembled the classic curves of superconductors. Upon heating to 130 °C, the effect did not disappear, and extrapolation of the data suggested that the property might persist even at 700 °C. However, direct proof of zero resistance has not yet been obtained: when pressed into pellets, the superconducting signs disappeared.
The authors themselves emphasize the preliminary nature of the conclusions and call on the scientific community to verify them. If the results are confirmed, this could open the way to new types of conductors based on abundant carbon, without complex rare-earth elements or extreme pressures.
The discovery is a reminder of how little we still know about everyday materials and how simple manipulations sometimes lead to unexpected quantum effects.
