Comparison of 3D-Structured and Mesoporous Carbon as Host Material for Conversion/Alloy Active Material-Anodes with ZnO Using Operando Methods

The performance of mesoporous and three-dimensional (3D)-structured carbon as host materials for zinc oxide (ZnO) in conversion/alloy active material-anodes is investigated and compared. Utilizing a variety of advanced operando characterization techniques such as dilatometry, confocal microscopy, online mass spectroscopy and multiple other classical characterization techniques, the structural and electrochemical properties of ZnO deposited on different carbon scaffolds are characterized. Our results indicate significant differences in aging, namely volume expansion and gas formation during cycling, between the two different types of host materials. Specifically, ZnO on mesoporous carbon (“ZnO@C-porous”) exhibited less volume expansion but higher gas evolution, suggesting more side reactions with the electrolyte. Conversely, ZnO on 3D-structured carbon (“ZnO@C-mesh”) showed more volume expansion but reduced gas formation, highlighting the distinct mechanisms and potential advantages of each material in battery applications. Our findings provide critical insight for optimizing anode materials in high-performance energy storage systems.