Rational tailoring of architectures and microenvironment on MOFs/natural clay hybrid materials for efficiently boosted performance of hybrid proton exchange membranes

Abstract

AbstractMetal–organic frameworks (MOFs) is now becoming the most fascinating conductive materials due to designable structure and pores at molecular level, and available crystal structure for the study of conduction mechanism. Nevertheless, comparing to the design of molecular structures of MOFs, the hybrid of MOFs with special micro/nano‐structured materials is considered to be a more effective approach for improved properties. In this study, the PAT@UiO‐66‐SO3H hybrid material was constructed with high conductive UiO‐66‐SO3H, a famous kind of MOFs, and polydopamine‐coated natural clay attapulgite (PAT), then the prepared hybrid material was blended with chitosan (CS) to prepare proton exchange membranes (PEMs). Owing to the special architectures and microenvironment, combining with the advantages of composition with UiO‐66‐SO3H and attapulgite, the prepared composite membranes showed considerable improved performances, including tensile strength, thermal and structural stability, fuel resistance ability, conduction and single cell performances. The CS/PAT@UiO‐66‐SO3H‐5 composite membrane exhibited the highly enhanced tensile strength of 67 MPa and improved thermal stability with Tg value of 235°C, as well as the lowest methanol crossover value of 1.2 × 10−6 cm2 s−1. Besides, the highest proton conductivity of 38.8 mS cm−1 at 80°C and power density of 37.9 mWcm−2 was achieved with CS/PAT@UiO‐66‐SO3H‐3 composite membrane, these performances were higher than pristine CS of 22.7 mS cm−1 and 32.2 mW cm−2 respectively. Our investigation reveals great application potential of MOFs based hybrid materials in fabricating of high performance composite PEMs.Highlights PAT@UiO‐66‐SO3H hybrid materials were constructed from MOFs and natural clay. The hybrid materials possessed special architectures and microenvironment. The PAT@UiO‐66‐SO3H introduced consecutive channels and proton sites. The hybrid membranes achieved excellent performances.