Concurrent realization of dendrite-free anode and high-loading cathode via 3D printed N-Ti3C2 MXene framework toward advanced Li–S full batteries

Abstract

The practical implementation of Li–S battery has been equally hampered by uncontrollable dendritic growth at the anode and inferior high-loading performance at the cathode. It is therefore desirable to explore multifunctional host candidate coupled with advanced fabrication technique to concurrently modulate both electrodes. Herein, we propose a versatile 3D printed (3DP) framework comprising nitrogen-doped porous Ti3C2 MXene (N-pTi3C2Tx) that is competent in regulating dual electrodes of Li–S batteries. Such a 3DP scaffold possesses hierarchical porosity, high conductivity, as well as ample nitrogen sites to synergize lithiophilic-sulfiphilic feature. Serving as a dendrite inhibitor, 3DP N-pTi3C2Tx interlayer could dissipate the local current and homogenize Li deposition, accordingly rendering a dendrite-free anode to maintain an ultralong lifespan up to 800 h at 5.0 mA cm–2/5.0 mAh cm–2. Meanwhile, the 3DP N-pTi3C2Tx host enables suppressed polysulfide shuttle and accelerated sulfur electrochemistry especially under elevated sulfur loadings. Thus-printed Li–S full cells (3DP N-pTi3C2Tx/S||3DP N-pTi3C2Tx@Li) can continuously operate over 250 cycles at a sulfur loading of 7.56 mg cm–2, accompanied by a capacity decay of 0.06% per cycle. More impressively, an ultimate capacity of 8.47 mAh cm–2 is harvested after 60 cycles at 12.02 mg cm–2.