The quality and depth of the analysis here far exceeds the work done by the original Korean team. It is very unlikely the Korean team has successfully manufactured the Cu-doped phase given the thermodynamic mountain required to climb, and its clear anybody attempting to replicate their recipe was essentially producing a random assortment of garbage.
The Korean team needs to disclose any alternative formulations or just accept failure and move on.
The Korean team needs to disclose any alternative formulations or just accept failure and move on.