Historical research guide · 0614 · 2014
The Pd + D Co-Deposition: Process, Product, Performance
Stanislaw Szpak
In one minute
Stanislaw Szpak spent his working life at the US Navy’s SPAWAR laboratory in San Diego, and in May 1989 he proposed a different way to build a Fleischmann–Pons electrode. Instead of loading deuterium into a solid palladium rod over days or weeks, plate the palladium and the deuterium down together out of a heavy-water solution of palladium chloride, onto a substrate that absorbs no deuterium at all — copper, gold or platinum. The film arrives already loaded. This paper is his account of the whole method: the electrode chemistry, the porous cauliflower-shaped deposit it grows, and what that deposit does once it runs. He reports deuterium-to-palladium ratios at and above one within seconds, a structure that reshapes itself when the cell is placed in an external electric or magnetic field, and infrared images of short-lived hot spots scattered across the surface, each strong enough to register on a piezoelectric substrate underneath as a pressure wave. His reading is that the heat is released at discrete sites inside the lattice, not evenly through the electrode.
Connection
Chapter 12 is about getting deuterons close enough together inside a metal lattice for tunnelling to matter, and co-deposition is the technique that makes that loaded condition arrive in seconds instead of weeks. The infrared hot-spot imaging is also the closest thing this line of work has to a picture of where the energy actually comes out.
From the source
Co-deposition electroplates palladium ions and deuterium ions together onto a substrate that does not absorb deuterium, such as copper, gold or platinum, which removes the long charging time a solid palladium electrode needs before it can be studied.Section 1, Introduction; Section 2, Process
Deuterium uptake measured by reversing the cell current gives deuterium-to-palladium atomic ratios of 0.95, 1.07, 1.1 and 1.3 after 1, 2, 4 and 8 seconds of charging, so the co-deposited film reaches an atomic ratio of one immediately and then passes it.Section 2.3, Corollary items 2 and 3; Fig. 2
The cauliflower-like structure of the deposit is unchanged by cathodic current densities up to 400 milliamps per square centimetre, but placing the operating cell in an external electric field re-forms it into columns of globules aligned with the field, and a magnetic field flattens the globules into pancake-like entities fixed to the substrate.Section 3.1, Structure: Effect of external fields; Fig. 3
Infrared imaging of a working electrode shows discrete short-lived hot spots distributed randomly in time and space, and a pressure-sensitive substrate beneath the film registers the pressure and temperature wave from each one, so the heat source is localised at reaction sites rather than spread uniformly through the electrode volume.Section 4.1, Infrared imaging and pressure and temperature wave; Fig. 5
Co-deposition begins with the endothermic absorption of deuterium, and within seconds that absorption is balanced by an exothermic reaction, after which the exothermic term dominates the thermal record.Section 4.2, Initial thermal behavior; Fig. 6
Szpak’s proposed mechanism is ordered clusters of deuterons gathering around lattice defects and releasing energy through a fast chain of nuclear reactions or a cluster collapse; his own named test is that the hot spots brighten as the solution warms from 30 to 80 degrees Celsius, a range over which nuclear reaction rates should not change, which points to either the chain-reaction rate constant or the cluster size being temperature dependent.Section 4.3, Corollary; Section 5.1, Kinetic aspects at the start of co-deposition
The way in
https://doi.org/10.70923/001c.72316How to cite it
Stanislaw Szpak (2014) The Pd + D Co-Deposition: Process, Product, Performance doi:10.70923/001c.72316