Laser-hybrid fabrication of highly-dispersed substrate-bonded manganese carbonate microspheres

• We have fabricated MnCO3 microspheres by laser cladding coupled with dealloying.
• The MnCO3 microspheres grow directly out of the laser cladded Cu-Mn alloy layer.
• The MnCO3 microspheres are highly-dispersed, creating large specific surface area.
• The fabricated MnCO3 microspheres are conducive to electrode applications.

Development of binder-free electrode materials tightly bonded to current collector effectively improves the performance of energy conversion and storage devices. In this letter, we report the fabrication of highly-dispersed MnCO3 microspheres directly grown out of a laser cladded substrate through dealloying process. First, laser cladding of Cu and Mn powder mix creates a layer of single-phase Cu–Mn alloy on a stainless steel substrate. Next, during dealloying, Mn is preferentially oxidized on the surface of the Cu-Mn alloy layer where the MnCO3 nuclei instantaneously form and subsequently grow into hierarchical microspheres. The high dispersivity of MnCO3 microspheres signifies a large specific surface area, which is highly desirable as an electrode material. Additionally, our unique hybrid fabrication approach eliminates the need for adhesive between the electrode material and its supporting substrate, and thus minimizing the interface resistance.