posted on 2024-01-11, 14:03authored byChengdong Xie, Kaili Zhang, Yongyong Lai, Lili Du, Ji Ma, Shouwu Xu, Ping Qiu
In water splitting processes, the oxygen evolution reaction
(OER)
is one of the main kinetic control steps that should be triggered
by high-efficiency catalysts. A series of Cu-based catalysts are considered
potential candidates. This work provides a simple and effective strategy
for fabricating large-scale copper-based catalysts by anodization
on a copper foil at room temperature in a KOH solution. The representative
petal-shaped CuO and Cu(OH)2 nanorods are obtained. The
corresponding surface areas are 0.0197 and 1.966 m2/g,
respectively. The surface wettability of Cu(OH)2 is lower
than that of CuO. The catalytic performance is studied by linear sweep
voltammetry (LSV). The results show that the potential of the OER
for CuO at 10 mA/cm2 is 1.67 V, which reduces by 130 mV
compared to Cu(OH)2. The CuO could keep 10 mA/cm2 after a 1 h chronoamperometry test, which is about 3 times higher
than that of Cu(OH)2. To verify the distinguishing catalytic
difference between CuO and Cu(OH)2, in situ Raman spectra
have been recorded. Inspiringly, the CuIII active specie
at 603 cm–1 is captured during the OER process on
CuO instead of Cu(OH)2. The related mechanism has been
discussed in detail.