Shear-flow induced alignment of graphene enables the closest packing crystallography of the (002) textured zinc metal anode with high reversibility

Abstract

The crystallographic orientation of Zn metal is related to its deposition pattern, plating/stripping reversibility, the HER and corrosion. Herein, theoretical calculations show that the (002) crystal plane of Zn metal not only is beneficial for the reversibility of Zn plating/stripping and inhibition of dendrites, but also inhibits the HER and alkaline corrosion. A meter-scale graphene-modified copper collector (Cu@G) was continuously prepared using shear-flow induction. The Cu@G collector selectively locks the lattice orientation of Zn deposits, enabling the closest packing crystallography of the (002) textured Zn metal anode. The SEM electron backscattered diffraction (EBSD) and XRD results show that Zn was deposited on the surface of the Cu@G collector with an ultra-high and uniform (002) orientation. Electrochemical test results show that the Cu@G collector exhibits excellent plating/stripping reversibility and a superior cumulative plating capacity (>6900 cycles at 40 mA cm⁻² with 2 mA h cm⁻², an ACE of up to 99.977%, and a CPC of up to 13 860 mA h cm⁻²). Zn²⁺ hybrid supercapacitors (ZHSs) and zinc ion batteries (ZIBs) also show excellent performance (ZHSs can be recycled >48 000 times with a capacity retention ratio of 94.6% and an ACE close to 100%; the capacity retention ratio of a Zn//PANI full cell is 80.43% after 130 cycles with a CE of 100% at N/P = 2.35). We also demonstrate an anode-free design (i.e., zero-excess Zn) with a modified Cu@G collector, and this Zn-manganese (MnO₂) double-plated cell assembled with Cu@G and carbon cloth maintains a stable cycling capacity for nearly 100 cycles at a high areal capacity of 5 mA h cm⁻² with a capacity retention ratio of nearly 100%. This work provides the possibility of high Zn utilization anode or Zn metal-free anode design for Zn-based batteries in energy storage systems.