SELF-ASSEMBLY OF COATINGS UTILIZING SURFACE CHARGE

摘要

An apparatus and method for measuring the isoelectric pH for materials deposited on or otherwise affixed onto and in contact with an electrode surface, and a method for utilizing the isoelectric pH to form nanometer thickness, self-assembled layers on the material, are described. Forming such layers utilizing information obtained about the isoelectric pH values of the substrate and the coating is advantageous since the growth of the coating is self-limiting because once the surface charge has been neutralized there is no longer a driving force for the solid electrolyte coating thickness to increase, and uniform coatings without pinhole defects will be produced because a local driving force for assembly will exist if any bare electrode material is exposed to the solution. The present self-assembly procedure, when combined with electrodeposition, may be used to increase the coating thickness. Self-assembly, with or without additional electrodeposition, allows intimate contact between the anode, electrolyte and cathode which is required for successful application to solid-state batteries, as an example.

主权项

1. An apparatus for determining the isoelectric pH of a material, comprising in combination:
a first chamber adapted for containing a solution having a chosen pH comprising:
a circular disk having an axis, a first face, and an opposing second face onto which said material is disposed;a shaft attached to the first face of said disk;a first reference electrode disposed in the vicinity of the second face of said disk and in the vicinity of the axis; anda hollow tube affixed to a wall of said first chamber at an orifice therein; a second chamber in fluid communication with said first chamber through said tube, comprising a second reference electrode; means for rotating said shaft at a chosen rate; and means for measuring the potential difference between said first reference electrode and said second reference electrode.