Metal Organic Framework Nanosheets: A Promising Solution for Self

A research team from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) has introduced a new strategy using metal organic framework (MOF) nanosheets as ion carriers to achieve self-optimized zinc anodes. This breakthrough has the potential to overcome the challenges faced by aqueous rechargeable zinc ion batteries, particularly the poor reversibility of the zinc anode caused by dendrite formation and side reactions.

The team led by Prof. Yang Weishen and Dr. Zhu Kaiyue found that MOF nanosheets possess unique properties that make them suitable for this application. Their one-dimensional channel structure allows for the migration of Zn2+ ions under an electric field, while their preferential Zn2+ adsorption enables them to serve as efficient Zn2+ ion carriers. Moreover, the weak coordination between ligands and zinc ions in MOF nanosheets contributes to their reductive chemistry, which helps optimize the zinc electrode during cycling.

During the cycling process, the MOF nanosheets gradually reconstruct the zinc anode, resulting in a horizontally aligned lamellae-like morphology and enhanced texture. This is attributed to the horizontal alignment of Zn2+ ions by the constraints of the MOF nanosheets. Additionally, the presence of MOF ligands aids in the elimination of undesirable byproducts, which are converted into useful MOF nanosheets. As a result, the zinc anode shows improved cycling performance in both low and high-rate conditions.

This research demonstrates the promising potential of the “ion carrier” strategy using MOF nanosheets for achieving highly reversible cycling in rechargeable metal cells. The versatility of this approach allows for its broad applicability to various ligands, substrates, and electrolytes. It opens up possibilities for the development of more efficient and durable battery systems for electric grid storage and other applications.

Sources:– Energy & Environmental Science (DOI: 10.1039/D3EE01747H)– Chinese Academy of Sciences