Achieving Highly Proton-Resistant Zn-Pb Anode through Low Hydrogen Affinity and Strong Bonding for Long-Life Electrolytic Zn//MnO2 Battery

摘要

High-energy electrolytic Zn//MnO2 batteries show potential for grid-scale energy storage, but the severe hydrogen evolution corrosion (HEC) caused by acidic electrolytes results in subdued durability. Here, an all-around protection strategy is reported for achieving stable Zn metal anodes. First, a proton-resistant Pb-containing (Pb and Pb(OH)(2)) interface is constructed on a Zn anode (denoted as Zn@Pb), which in situ forms PbSO4 during H2SO4 corrosion and protects the Zn substrate from HEC. Second, to improve the plating/stripping reversibility of Zn@Pb, Pb(CH3COO)(2) an additive (denoted as Zn@Pb-Ad) is introduced, which triggers PbSO4 precipitation and releases trace Pb2+ that can dynamically deposit a Pb layer on the Zn plating layer to suppress HEC. The superior HEC resistance stems from the low affinity of PbSO4 and Pb for H+, as well as strong bonding between Pb-Zn or Pb-Pb, which increase the hydrogen evolution reaction overpotential and the H+ corrosion energy barrier. Consequently, the Zn@Pb-Ad//MnO2 battery runs stably for 630 and 795 h in 0.2 and 0.1 m H2SO4 electrolytes, respectively, which are >40 times better than that of bare Zn. The as-prepared A h-level battery achieves a one-month calendar life, opening the door to the next generation of high-durable grid-scale Zn batteries.

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