Electrochemical performance of Sn-doped δ-MnO2 hollow nanoparticles for supercapacitors

Sn-doped δ-MnO2 (Sn-MnO2) hollow nanoparticles have been synthesized via chemical process at room temperature. Many characterizations have been carried out to fully identify the intrinsic information of the as-prepared samples and investigate their electrochemical properties. The results indicate that the morphologies of the samples can be adjusted by changing the concentration of Sn while the capacitance of Sn-MnO2 nanoparticles increased corresponded with that of the undoped δ-MnO2 nanoparticles. The specific capacitance of Sn(1 at.%)-MnO2 is up to 258.2 F g− 1 at a current density of 0.1 A g− 1. What’s more, over 90% of the initial specific capacitance still remains after 1000 cycles at a current density of 2.0 A g− 1, displaying excellent cycling stability.