Figure 2.

HAADF-STEM images of Pd–Cu alloy NCs supported on Al₂O₃ and corresponding EDX maps for Cu and Pd after (a) oxidizing and (b) reducing treatments; (c) azimuthally integrated, background-subtracted SAED patterns after oxidation and reduction in comparison to Pd–Cu NCs (reference patterns: Pd₁Cu₁ ICSD 103082 (black line), Pd₁O₁ ICSD 24692 (green line), and γ-Al₂O₃ ICSD 100425 (red line)). The reference pattern for Cu_0.3Pd_0.7O was calculated by modifying the tetragonal cell of PdO (ICSD 24692). The new cell had Cu and Pd ions with fractional occupancies (0.3 and 0.7, respectively) in the sites of Pd ions and parameters, a = b = 3.005 Å and c = 5.29 Å, calculated according to the plots in ref (45) for Cu_xPd_1–xO, with x = 0.3).