Extended Data Fig. 5: Transmission electron microscopy (TEM) measurements.
From: Multifunctional ytterbium oxide buffer for perovskite solar cells
a, b, TEM images of YbOx directly deposited on the carbon-supported copper (50 and 20 nm). c, The typical fast Fourier transform (FFT) spectrum (30 × 30 nm2 area) indicates the amorphous crystal structure of YbOx.
