High performance δ-Bi2O3 nanosheets transformed Bi2S3 nanoflakes interconnected nanosheets as negative electrode for supercapacitor applications

•Bismuth oxide (δ-Bi2O3) with high specific capacitance has emerged as a promising negative electrode material for supercapacitors.•δ -Bi2O3 nanosheets followed by hydrothermal route.•δ-Bi2O3 nanosheets electrode has only reached to 474 F g−1 for 1 A g−1 with poor retention of 46%.