Hygroscopic holey graphene aerogel fibers enable highly efficient moisture capture, heat allocation and microwave absorption

Yinglai Hou,Zhizhi Sheng,Xuetong Zhang,Jie Kong,Chen Fu

doi:10.1038/s41467-022-28906-4

Abstract

Aerogel fibers have been recognized as the rising star in the fields of thermal insulation and wearable textiles. Yet, the lack of functionalization in aerogel fibers limits their applications. Herein, we report hygroscopic holey graphene aerogel fibers (LiCl@HGAFs) with integrated functionalities of highly efficient moisture capture, heat allocation, and microwave absorption. LiCl@HGAFs realize the water sorption capacity over 4.15 g g−1, due to the high surface area and high water uptake kinetics. Moreover, the sorbent can be regenerated through both photo-thermal and electro-thermal approaches. Along with the water sorption and desorption, LiCl@HGAFs experience an efficient heat transfer process, with a heat storage capacity of 6.93 kJ g−1. The coefficient of performance in the heating and cooling mode can reach 1.72 and 0.70, respectively. Notably, with the entrapped water, LiCl@HGAFs exhibit broad microwave absorption with a bandwidth of 9.69 GHz, good impedance matching, and a high attenuation constant of 585. In light of these findings, the multifunctional LiCl@HGAFs open an avenue for applications in water harvest, heat allocation, and microwave absorption. This strategy also suggests the possibility to functionalize aerogel fibers towards even broader applications.

Highlights

Aerogel fibers have been recognized as the rising star in the fields of thermal insulation and wearable textiles
LiCl is selected as the active salt decorated within the fiber because of its low density, low dehydration temperature, and super high water sorption capacity[17]
LiCl@holey graphene aerogel fiber (HGAF) are further demonstrated with outstanding water harvest, heat allocation, and microwave adsorption behavior (Fig. 1b)

Summary

Introduction

Aerogel fibers have been recognized as the rising star in the fields of thermal insulation and wearable textiles. We report hygroscopic holey graphene aerogel fibers (LiCl@HGAFs) with integrated functionalities of highly efficient moisture capture, heat allocation, and microwave absorption. In light of these findings, the multifunctional LiCl@HGAFs open an avenue for applications in water harvest, heat allocation, and microwave absorption This strategy suggests the possibility to functionalize aerogel fibers towards even broader applications. The holey graphene aerogel porous matrix provides sufficient binding sites and surface area for water uptake and abundant water transport pathways through the etched nanopores These LiCl@HGAFs exhibit 4.15 g g−1 moisture sorption capacity at 90% relative humidity and multiple pathways to perform sorption/desorption processes, and thermodynamics and kinetics of the water sorption with the LiCl@HGAFs are determined. Benefitting from moisture sorption performance, LiCl@HGAFs are demonstrated as adsorption-based heat transfer (AHT)

Methods

Results

Conclusion