A novel 3D heterostructure of carbon aerogel nanospheres embedded in ultrathin MoSe2 nanoslices is synthesized by a simple method. The morphologies and structure of obtained sample are thorough characterized. Benefiting from the peculiar cross-connected nanostructure, the MoSe2 nanoslices-carbon aerogel nanospheres hybrids exhibit high specific capacity of 775.3 C g(-1) and good cycling stability (keeping 98% of initial specific capacity) after 1500 cycles at 1 A g(-1) in 6 mol L-1 KOH, demonstrating hierarchical MoSe2 nanosheets-carbon aerogel nanospheres hybrids are the high-performance super-capacitor electrode material. Furthermore, the as-prepared materials show an enhanced performance toward the electrochemical sensing of endocrine disruptors 17 beta-estradiol with a linear range of 0.005-5 nmol L-1 and a detection limit as low as 2.0 x 10(-13) mol L-1 (signal to noise of 3). The encouraging results herein ensure the merits of cross-connected nanostructure. Furthermore, it is beyond all doubt that this work provides a promising preparation strategy to develop transition metal selenides based nano-architecture for energy storage and electrochemical sensing. (C) 2017 Elsevier Ltd. All rights reserved.