학술논문

Ni electrodes with 3D-ordered surface structures for boosting bubble releasing toward high current density alkaline water splitting
Document Type
article
Source
Ultrasonics Sonochemistry, Vol 96, Iss , Pp 106398- (2023)
Subject
Alkaline water electrolysis
Gas bubble
3D-ordered surface structures
Durability
High-speed camera
Chemistry
QD1-999
Acoustics. Sound
QC221-246
Language
English
ISSN
1350-4177
Abstract
The performance of alkaline water electrolysis (AWE) at high current densities is limited by gas bubble generation on the surface of electrodes, which covers active sites and blocks mass transfer, resulting in lower AWE efficiency. Here, we utilize electro-etching to construct Ni electrodes with hydrophilic and aerophobic surfaces to improve the efficiency of AWE. Ni atoms on the Ni surface can be exfoliated orderly along the crystal planes by electro-etching, forming micro-nano-scale rough surfaces with multiple crystal planes exposed. The 3D-ordered surface structures increase the exposure of active sites and promote the removal of bubbles on the surface of the electrode during the AWE process. In addition, experimental results from high-speed camera reveal that rapidly released bubbles can improve the local circulation of electrolyte. Lastly, the accelerated durability test based on practical working condition demonstrates that the 3D-ordered surface structures are robust and durable during the AWE process.