Perovskite structures are notorious for breaking down very rapidly in real-world use. Now a research team from Princeton University has developed a process for overcoming that problem, making perovskite a real competitor to existing silicon PV technology.
https://en.wikipedia.org/wiki/Perovskite_solar_cell
Key takeaway of the wiki article:
This new advancement might fix their biggest flaw.
A graph showcasing the recent rapid progress with perovskite solar cell technology:
https://upload.wikimedia.org/wikipedia/commons/3/33/ModulePVeff(rev200708).png