The research only involved the synthesis and catalytic evaluation of the solids obtained in laboratory conditions
They used the sol-gel method. You don't use solids there. And ethanol is in liquid form as far as I know.
it showed a high conversion and selectivity, higher than 80%; so we can continue investigating this system to expand the information.
The graphical abstract on your source already mentions the answer "Up to 86% conversion with 97% selectivity". And it's not just plain Copper used but "oxide-derived" Copper compounds, that's why Aluminum and Zirconium were mentioned. I think you also may be interested in this Ethanol from Copper Catalyst too.