[1] For example, this 5.13% PCE from "hierarchical barium titanate micro flowers": https://iopscience.iop.org/article/10.1088/2053-1591/aace86
They also compare photocurrents under a solar simulator and achieve 100x increase vs bulk BTO.
At no point do they make comparison to state of the art BTO cells, which almost certainly aren't just bulk BTO but are likely doped, nanostructured, or have some other novelty.
> Our apologies for not making this clear. The photovoltaic effect was increased by 1000 times compared to previous output achieved from cells made of ferroelectric crystals, not from prevailing solar cells made of silicon or other conventional materials.
misleadingly make it seem like they made 1000x progress from the current best.
> Our apologies for not making this clear. The photovoltaic effect was increased by 1000 times compared to previous output achieved from cells made of ferroelectric crystals, not from prevailing solar cells made of silicon or other conventional materials.
Even if they made the best theoretically possible solar cell, the starting point of 1/1000th of that would not have been considered useful for anything.