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

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-pTi(3)C(2)T(x)) 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-pTi(3)C(2)T(x) 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-pTi(3)C(2)T(x) host enables suppressed polysulfide shuttle and accelerated sulfur electrochemistry especially under elevated sulfur loadings. Thus-printed Li-S full cells (3DP N-pTi(3)C(2)T(x)/S parallel to 3DP N-pTi(3)C(2)T(x)@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).

Automated summary

A multifunctional 3D printed framework comprising nitrogen-doped porous Ti3C2MXene is proposed to regulate both electrodes of Li-S batteries. The framework possesses high conductivity and ample nitrogen sites for synergizing lithiophilic-sulfiphilic feature.