Molecular\nFilter Net Synergy with Regulation in Ion\nPercolation for High-Performance Zn Metal Batteries

The\nuncontrollable dendrite growth and complex parasitic reactions\nof Zn metal anodes cause short cycle lives and low Coulombic efficiency,\nwhich seriously affect their applications. To address these issues,\nthis research proposes an efficient ion percolating interface constituted\nby a hydrogen-bonded organic framework (HND) for a highly stable and\nreversible Zn anode. The hydrogen-bonded skeleton acts as a molecular\nfilter net, capturing water molecules by forming targeted hydrogen-bonding\nsystems with them, sufficiently inhibiting parasitic reactions. Additionally,\nthe interaction of the rich-N and -O electrochemically active sites\nwith Zn<sup>2+</sup> effectively regulates its percolation, which\ngreatly enhances the diffusion kinetics of Zn<sup>2+</sup>, thus facilitating\nrapid and uniform migration of Zn<sup>2+</sup> at the anode surface.\nThrough the above synergistic effect, dendrite-free anodes with highly\nreversible Zn plating/stripping behaviors can be achieved. Hence,\nthe modified Zn anode (HND@Zn) performs a steady cycling time of more\nthan 1700 h at 1 mA cm<sup>–2</sup>. Moreover, the HND@Cu||Zn\nasymmetric cell exhibits a stable charge/discharge process of over\n1600 cycles with an average Coulombic efficiency of up to 99.6% at\n5 mA cm<sup>–2</sup>. This work provides some conceptions for\nthe evolution and application of high-performance Zn metal batteries.