PFDT Self-Assembled Monolayers for Stable Zinc Anodes in Aqueous Batteries

High Resolution Image Download MS PowerPoint Slide Aqueous zinc-ion batteries (AZIBs) have emerged as important candidates for next-generation energy storage systems due to the abundance of zinc resources, high theoretical capacity (820 mAh g –1 ), good safety, and low cost. However, zinc dendrite growth and corrosion issues severely hinder their practical application. This study prepared a PFDT@Zn-modified electrode by self-assembly of 1 H,1 H,2 H,2 H -perfluorodecanethiol (PFDT) on the zinc anode surface. A series of electrochemical performance tests, characterizations, and density functional theory (DFT) calculation results indicate that PFDT forms an ordered perfluorocarbon chain protective layer on the zinc surface via Zn–S covalent bonds, and its strong hydrophobicity blocks electrolyte contact and inhibits hydrogen evolution and corrosion reactions; the C–F bonds construct δ−F···Zn 2+ zincophilic sites, enhancing the Zn 2+ transport rate and transference number and optimizing the interfacial electric field distribution; PFDT – drives Zn 2+ to deposit preferentially on the low-energy Zn(002) crystal plane through selective adsorption on high-energy crystal planes, thereby achieving dense deposition. Electrochemical tests show that the PFDT@Zn symmetric cell stably cycled for 1750 h at 0.5/0.5 mAh cm –2 and for 3600 h at 5/1 mAh cm –2, while the bare Zn only cycled for 431 h. The Coulombic efficiency of Zn||Cu asymmetric cell reached 99.7% after 2000 cycles. The full cell assembled with MnO 2 as the cathode maintained 83.6% capacity retention after 900 cycles at 1 A g –1, with a 48 h static self-discharge rate of 0.15%. These research findings can provide a basis for designing reversible zinc anodes with high cycling stability.