Two-Dimensional SnSe Nanonetworks: Growth and Evaluation for Li-Ion Battery Applications

Engineered two-dimensional (2D) layered materials possess unique physical properties with the potential to improve the performance and endurance of future electronic and energy devices. Here, we report the growth of complex 2D nanonetworks of crystalline tin selenide (SnSe) via liquid injection chemical vapor deposition using a single-source diselenoether precursor. Potential applications of SnSe span a wide range of technological areas, particularly in energy devices. The synthesized SnSe networks were composed of high surface area interconnected junctions of one-dimensional (1D) nanowires in a 2D plane; such complex SnSe nanonetwork structures have not previously been reported. The SnSe networks possessed an orthorhombic Pnma 62 crystal structure throughout, with the individual network branches uniformly orientated along the <011> and <01-1> directions. The width of the individual interconnected nanowire branches ranged from 120 to 250 nm with lengths ranging from 1 to 4 μm. The networks of 1D nanowires had a layer thickness of 88 ± 10 nm. A growth mechanism for the formation of these networks is proposed based on the minimization of high surface energy planes. We also highlight the potential of SnSe nanonetworks as an anode material for Li-ion batteries with galvanostatic testing showing an initial discharge capacity in excess of 1000 mAh g-1 with a 92% capacity retention after 50 cycles at a specific current of 100 mA g-1.