TY  - JOUR
AU  - Wang, Zheng
AU  - Wang, Hanxiao
AU  - Jiang, Runlai
AU  - Wang, Hui
AU  - Ren, Jianwei
AU  - Wang, Xuyun
AU  - Liu, Jian
PY  - 2026
TI  - Cassie-impregnated interface design enables efficient O2 bubble mass transfer in NiCo2O4 array electrodes
JO  - Nano Research
SN  - 1998-0124
SP  - 94908951
VL  - 19
IS  - 11
AB  - Three-dimensional array structures are recognized as hydrophilic and gas-repellent architectures for water electrolysis electrodes. In reported studies, the interfacially accelerated bubble detachment process is generally attributed to the role of the gas–liquid–solid three-phase contact line under the ideal Wenzel model, while in-depth investigations into bubble dynamics under the practically occurring Cassie-impregnating mode remain scarce. In this study, a stable Cassie-impregnating wetting state was constructed and optimized via regulation of the depth in NiCo2O4 nanowire arrays. As the array depth increases from 1.43 to 4.14 μm, the wettability and gas-repellent performance exhibit a “volcano-type” trend, with a maximum underwater bubble contact angle of 150° and a minimum bubble adhesion force of 9.51 μN. Dynamic bubble statistics reveal that at 100 mA·cm−2, the optimized NiCo2O4 nanowire array delivers a high O2 bubble generation rate of 107 cm−2·s−1 for bubbles with an average size of ~ 120 μm. The mass transport overpotential for the oxygen evolution reaction (OER) on the NiCo2O4 nanowire electrode is reduced to 157 mV at 300 mA·cm−2. Moreover, the anion exchange membrane water electrolyzer delivers a cell voltage of only 1.81 V at a current density of 1000 mA·cm−2, while maintaining stable operation for more than 400 h.
UR  - https://doi.org/10.26599/NR.2026.94908951
DO  - 10.26599/NR.2026.94908951