Chemists at Rice University have replicated Thomas Edison's 1879 light bulb experiments and found evidence that the inventor may have accidentally produced graphene as a byproduct. The discovery, detailed in a new paper, highlights how modern tools can reinterpret historical innovations. This turbostratic graphene emerged from heating carbon filaments to extreme temperatures.
In the late 1870s, Thomas Edison worked at his Menlo Park laboratory to perfect the incandescent light bulb for commercial use. Early filaments, such as carbonized cardboard and lampblack, burned out quickly, as did those from grasses like hemp and palmetto. Edison eventually settled on carbonized bamboo, which lasted over 1,200 hours on a 110-volt source.
A team led by chemist James Tour at Rice University revisited these experiments to explore affordable graphene production methods. Graduate student Lucas Eddy drew from Edison's original 1879 patent, using artisan bulbs with bamboo filaments—slightly thicker at 5 micrometers in diameter than Edison's originals. By connecting them to a 110-volt power source for 20 seconds, the filaments reached 2,000 to 3,000 degrees Celsius, the threshold for flash Joule heating that yields turbostratic graphene.
Initial attempts with modern tungsten bulbs failed, but the Edison-style versions succeeded. The filament transformed into a 'lustrous silver,' and Raman spectroscopy confirmed turbostratic graphene formation. Transmission electron microscopy provided before-and-after images of the material.
'Finding that he could have produced graphene inspires curiosity about what other information lies buried in historical experiments,' Tour said. 'What questions would our scientific forefathers ask if they could join us in the lab today?'
The researchers note this is not conclusive proof, as Edison lacked detection tools, and any original graphene would have degraded to graphite. Still, the work opens doors to re-examining past technologies like vacuum tubes and arc lamps with today's materials science. The findings appear in ACS Nano (DOI: 10.1021/acsnano.5c12759), published January 24, 2026.