Sandwiched Li plating between Lithiophilic-Lithiophobic gradient Silver@Fullerene interphase layer for ultrastable lithium metal anodes

Constructing a multi-functionally artificial interphase layer is an emerging strategy to possibly address the issues of inhomogeneous Lithium (Li) nucleation and dendrite growth. In this study, a silver@fullerene (Ag@C 60 ) interphase layer with lithiophilic-lithiophobic gradient was designed, which was fabricated by series of deposition of silver and fullerene (Ag@C 60 ) on Cu foam current collector (ACCF). In this way, the typically uncontrolled Li deposition process will become a highly nucleation-guided process, due to the preferentially induced Li nucleation of Ag nanoparticles, which will guide the Li deposition sandwiched in C 60 and Ag layers. While the top lithiophobic fullerene layer is beneficial for regulating uniform Li-ion flux and facilitating the formation of LiF-rich SEI layer, finally suppressing the top deposition of Li metal, due to the high nucleation energy barrier on fullerene. Consequently, Li@ACCF exhibits a low overpotential of 14 mV and an ultra-stable cyclic life for more than 2500 h in symmetric cells. Besides, it also displays excellent long-term cycle life and high-rate performance in lithium-metal full cells. This deliberate design of the “push–pull” Li could ensure the uniform Li deposition sandwiched fullerene and silver layers and provide a feasible and efficient approach to advance the practical use of lithium-metal anodes for high-energy–density batteries.