Revisiting the cold case of cold fusion


The 1989 claim of ‘cold fusion’ was publicly heralded as the future of clean energy generation. However, subsequent failures to reproduce the effect heightened scepticism of this claim in the academic community, and effectively led to the disqualification of the subject from further study. Motivated by the possibility that such judgement might have been premature, we embarked on a multi-institution programme to re-evaluate cold fusion to a high standard of scientific rigour. Here we describe our efforts, which have yet to yield any evidence of such an effect. Nonetheless, a by-product of our investigations has been to provide new insights into highly hydrided metals and low-energy nuclear reactions, and we contend that there remains much interesting science to be done in this underexplored parameter space.

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Fig. 1: Revisiting cold fusion.
Fig. 2: Pressure–composition–temperature diagram for palladium hydride featuring the α-PdHx and β-PdHx phases.
Fig. 3: Detecting excess heat at high temperatures.
Fig. 4: Pulsed plasma apparatus.
Fig. 5: Motivation to explore nuclear fusion at lower energies.


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Students, postdoctoral researchers and staff responsible for advancing and supporting this project are listed as co-signatories in the Supplementary Information. P.A. Schauer, B. Lam, B.P. MacLeod, F.G.L. Parlane and A.K. Brown are gratefully acknowledged for their substantial contributions to the construction of this manuscript. The research supporting this Perspective was conducted with funding from Google LLC. Some aspects of the materials studies conducted at the University of British Columbia (UBC) were partially supported by the Canadian Natural Science and Engineering Research Council (CRD-502052-16) and made use of resources and facilities provided by the Canadian Foundation for Innovation (229288). A portion of the UBC research was conducted at: the 4D LABS shared facilities supported by the Canada Foundation for Innovation, British Columbia Knowledge Development Fund, Western Economic Diversification Canada, and Simon Fraser University; and the Centre for High-Throughput Phenogenomics at UBC, a facility supported by the Canadian Foundation for Innovation, British Columbia Knowledge Development Fund, and the UBC Faculty of Dentistry. Work at Lawrence Berkeley National Laboratory (Berkeley Lab) was performed under the auspices of the US Department of Energy (DE-AC02-05CH11231). Work at the Massachusetts Institute of Technology (MIT) used instrumentation in the Center for Materials Science and Engineering, a MRSEC Shared Experimental Facility supported by the National Science Foundation under award number DMR-14-19807. Some of the work at the University of Maryland (UMD) employed the shared facilities of the Maryland NanoCenter and its FabLab. The views and conclusions of authors expressed herein do not necessarily state or reflect those of the United States or Canadian Governments, or any agencies thereof.

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All authors outlined the manuscript. C.P.B. and M.D.T. wrote the manuscript. All authors reviewed and edited the entire manuscript.

Correspondence to Curtis P. Berlinguette or Matthew D. Trevithick.

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Berlinguette, C.P., Chiang, Y., Munday, J.N. et al. Revisiting the cold case of cold fusion. Nature 570, 45–51 (2019) doi:10.1038/s41586-019-1256-6

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