Ultrafast X-rays record proton movement

Researchers from the U.S. Department of Energy's Pacific Northwest National Laboratory, in collaboration with Stanford University's free-electron laser facility, revealed on October 6, 2026 a pioneering experiment whose results were published by the journal Science, recording the instantaneous trajectory of protons and electrons during chemical dissociation reactions in water.

The team used ultrashort X-ray laser pulses measured in fractions of a femtosecond, documenting for the first time the phenomenon of coupled proton-electron transfer in its transient dynamic state. The system focused on emitting X-ray pulses whose temporal duration does not exceed 50 femtoseconds to penetrate extremely thin liquid samples while being stimulated with ultraviolet light.

Advanced detectors recorded how adjacent water molecules interact and reorganize their structure within 100 femtoseconds of charge release, and how this synchronization directs the trajectory and rupture of chemical bonds without dissipating energy as waste heat, precisely mimicking biological mechanisms within plant photosynthesis reaction centers.

These atomic-scale observations open perspectives for designing low-cost artificial hydrogen catalysts that do not depend on rare metals such as platinum and iridium, as they allow the construction of electrodes that geometrically direct proton movement to achieve chemical conversion efficiency exceeding commercial models by percentages greater than 25 percent, in addition to developing liquid flow batteries.