Self-combustion induced hierarchical nanoporous alloy transition toward high area property electrode for supercapacitor

•The electrode is prepared by self-combusting a hierarchical nanoporous alloy.•Self-combustion impels FCC-type alloy transfer to mixed oxides with robust defects.•The high loaded electrode (7.8 mg cm−2) ensures rapid electron/ion transportation.•The symmetric supercapacitor delivers a high energy density of 0.17 mWh cm−2.