A novel process and apparatus to combinatorially screen a large number of discrete
compositions for electrocatalytic activity have been developed. The apparatus contains
a cell body adjacent to a fluid permeable catalyst array support supporting multiple
solids. A catalyst mask having holes that are in alignment with the multiple locations
for supporting solids is placed over the catalyst array support, masking the solids.
A cell cover is positioned adjacent to the catalyst array support, with the cell
cover having a passage for monitoring the solids through the mask. A detector may
be in alignment with the passage of the cell cover.
