The Effect of Tween Surfactants on Preparation of MnO₂ Nanostructures for Supercapacitors

In this paper, a novel MnO₂ nanostructure based on the nanowire interconnection between dandelion-type nanoglobules was prepared by a one-pot hydrothermal approach using Tween surfactants. For comparison, Tween 20, Tween 60, Tween 80 were respectively used in the synthesis of MnO₂ nanostructures. The formation mechanism as well as the difference in prepared structures were studied. It was worth noting that Tween 60 might promote the aggregation of nanoglobules, while Tween 80 might inhibit the aggregation of nanoglobules. The electrochemical characterization demonstrated that the specific capacitances of products prepared with Tween 20, Tween 60, Tween 80 for 6 h (T20-6, T60-6, T80-6) at the current density of 1 A g_-1 were 126.3, 154.2, 179.9 F g_-1, respectively. Furthermore, The T80-6 electrodes-based supercapacitors presented much higher specific capacitance than the other prepared β-MnO₂ nanostructures. This work provides an effective strategy for morphology tuning of nanomaterials applied in many fields, especially in energy applications.