Construction of Hierarchical MoSe2 Hollow Structures and Its Effecton Electrochemical Energy Storage and Conversion

Metal selenides have attracted increased attentionas promising electrode materials for electrochemical energy storageand conversion systems including metal-ion batteries and watersplitting. However, their practical application is greatly hindered bycollapse of the microstructure, thus leading to performance fading.Tuning the structure at nanoscale of these materials is an effectivestrategy to address the issue. Herein, we craft MoSe2withhierarchical hollow structures via a facile bubble-assistedsolvothermal method. The temperature-related variations of thehollow interiors are studied, which can be presented as solid, yolk−shell, and hollow spheres, respectively. Under the simultaneousaction of the distinctive hollow structures and interconnectionsamong the nanosheets, more intimate contacts between MoSe2and electrolyte can be achieved, thereby leading to superior electrochemical properties. Consequently, the MoSe2hollownanospheres prepared under optimum conditions exhibit optimal electrochemical activities, which hold an initial specificcapacity of 1287 mA h g−1and maintain great capacity even after 100 cycles as anode for Li-ion battery. Moreover, the Tafelslope of 58.9 mV dec−1for hydrogen evolution reaction is also attained.