Synthesis of Y3Ba5Cu8O18 superconductor powder by auto-combustion reaction: Effects of citrate-nitrate ratio

► A series of Y3Ba5Cu8O18 powders with different c/n values are prepared by auto-combustion reaction. ► This process transformed the precursor gels into ashes powder. ► Calcinations at 900 °C yield Y3Ba5Cu8O18 nanocrystalline powders. ► The c/n = 0.5 and 0.7 samples electrically superconducting at temperature above 100 K. ► This emphasized the importance of maintaining a stoichiometric or near stoichiometric reaction.