Figure 2

XRD spectra of the Cu-based microstructures formed during the solution reduction of Cu₂O at different reaction times.

(a) 0 min for non-porous Cu₂O microcubes, (b) 30 min for nanoporous Cu/Cu₂O/Cu dented cubic composites and (c) 70 min for hollow eightling-like Cu microparticles.