On March 23, 1989, while Pons was the chairman of the chemistry department at the University of Utah, he and Fleischmann announced the experimental production of "N-Fusion" which was quickly labeled by the press as cold fusion -- a result previously thought to be unattainable. After a short period of public acclaim, the pair were attacked widely for sloppy, irreproducible research and inaccurate results. Although some groups claimed to have reproduced their work, reviews by the US Department of Energy consider the claims to be unconvincing and declined to further fund the research.
Pons moved to France in 1992, along with Fleischmann, to work at the IMRA laboratory (part of Technova Corporation, a subsidiary of Toyota); the laboratory was closed in 1998 after burning through a $12 million research investment.. The pair parted ways in 1995. As of 1999, Pons was living in southern France. According to a report of the history of the chemistry department at the University of Utah, as of 2000 he is no longer doing research in France.