Post-synthetic modification strategy to immobilize acidic units within metal-organic frameworks or covalent organic frameworks for boosted proton conductivity

Abstract

Lately, a great deal of attention has been focused on the design and development of high-performance crystalline materials with excellent proton-conducting properties in domains such as proton screening, H-production, H-sensors, and biology, particularly fuel cells. Herein, we will summarize the enhancing effect on the proton conductivity of MOFs or COFs, focusing on two aspects: physical encapsulation of acidic molecules in the pores and chemical anchoring of acidic groups on the skeleton. The main discussion focuses on the specific approaches to loading acidic molecules, comparing proton conductivity, the difference in anchoring strategies, proton-conducting mechanism, and applications. Finally, based on the above discussion and our research experience, the future anchoring strategy and development trend are prospected, hoping to provide inspiration and guidance for researchers engaged in this field.