Influence of CeO2 content on electrochemical and discharge characteristics of aluminum air battery anode fabricated via SLM

To overcome the limitations of traditional aluminum anodes in Al-air batteries, this work fabricated CeO 2 /Al6061 anodes using selective laser melting (SLM) and examined the impact of CeO 2 content (0, 0.5, 1.0, and 1.5 wt.%) on their properties. Microstructural analysis (metallographic microscopy, SEM, EBSD, XRD) showed that CeO 2 incorporation significantly refined the grain structure. The 1.0 wt.% CeO 2 /Al6061 anode exhibited optimal performance, achieving 97.01% relative density, eliminating hot cracks and large pores, and forming a uniform cellular structure with an average grain size of 49.3 nm (74.9 nm for pure 6061). XRD confirmed the in-situ formation of Al 3 Ce intermetallic phases, which inhibited grain growth, and Mg 2 Si phases, which provided sacrificial anode protection. Electrochemical tests revealed that CeO 2 addition reduced the self-corrosion rate (SCR) and improved electrochemical activity. The 1.0 wt.% CeO 2 anode had the lowest SCR (58.6% lower than pure 6061), most negative corrosion potential (-1.634 V), and smallest corrosion current density (2.338×10 -2 A·cm -2 ). EIS results confirmed enhanced corrosion resistance. Discharge tests showed that the 1.0 wt.% CeO 2 anode delivered the highest and most stable discharge voltage, highest anode utilization rate (64.6%, 44.5% higher than pure 6061) and slowest voltage decay during 24h discharge. Excessive CeO 2 (1.5 wt.%) caused particle agglomeration and performance degradation, while insufficient CeO 2 (0.5 wt.%) failed to fully refine grains and inhibit corrosion. This work confirms that 1.0 wt.% CeO 2 is optimal for SLM-fabricated 6061 anodes, offering a viable strategy to enhance Al-air battery anode performance and expand their applications.