Fig. 3: Real-time imaging of CuO NS catalysts under electrochemical reaction.
In situ TEM imaging of catalyst structure during OCP in 30 µL/h H2O flow at a 2 s, b 50 s and c 110 s. The corresponding OCP profile is presented in Supplementary Fig. S15. The whole movie is shown as Supplementary Movie 1. d Current/potential profiles over time with marked time points, t1 - t4 (vertical lines), corresponding to the images in e–h. Linear sweep voltammetry (LSV) is performed after 10-second OCP measurement in a pH = 6.9 buffer solution flow (the OCP profile is given in Supplementary Fig. S17a) with scan rate of 50 mV/s. The following Chronoamperometry (CA) are acquired at −0.84 VRHE (the first potential). The whole movie is shown as Supplementary Movie 4. The corresponding images at i \(t_1^\prime\) = 2.5 s and j \(t_4^\prime\) = 460 s with the second LSV + CA (the 10-second OCP profile before LSV is given in Supplementary Fig. S17b) at −1.23 VRHE. Current/potential profiles over time with marked time points, \(t_1^\prime\) - \(t_4^\prime\) (vertical lines) and the images snapshots are shown in Supplementary Fig. S18. The whole movie is shown as Supplementary Movie 5. The corresponding images at k \(t_1^\prime\prime\) = 2.5 s and l \(t_4^\prime\prime\) =1000 s with the third LSV + CA (the 10-second OCP profile before LSV is given in Supplementary Fig. S17c) at −1.73 VRHE. Current/potential profiles over time with marked time points, \({t_1^\prime}\prime\) - \(t_4^\prime\prime\) (vertical lines) and the images snapshots are shown in Supplementary Fig. S19. The whole movie is shown as Supplementary Movie 6. m Schematic overview (time line) of the experimentally observed evolution of the CuO NS morphology probed by the in situ TEM E-chip flow cell, H-cell, and flow cell electrolyzer.
