Superprotonic Conductivity of Guanidinium Organosulfonate Hydrogen-Bonded Organic Frameworks with Nanotube-Shaped Proton Transport Channels
Xuyong Chen, Li‐Hui Cao, Xiang‐Tian Bai, Xiao‐Jie Cao, Dan Yang, Yi‐Da Gao
Abstract
High Resolution Image Download MS PowerPoint Slide Grasping proton transport pathways and mechanisms is vital for the application of fuel cell technology. Herein, we screened four guanidinium organosulfonate charge-assisted hydrogen-bonded organic frameworks (HOFs), namely, GBBS, G 3 TSPHB, G 4 TSP, and G 6 HSPB, which possess high hydrogen-bonded density proton transport networks shaped like nanotubes. These materials were prepared by self-assembly through charge-assisted interactions between guanidinium cations and organosulfonate anions, as well as by host–guest regulation. At 80 °C and 93% RH, the proton conductivity of GBBS, G 3 TSPHB, G 4 TSP, and G 6 HSPB can reach 4.56 × 10 –2, 2.55 × 10 –2, 4.01 × 10 –2, and 1.2 × 10 –1 S cm –1, respectively, with superprotonic conductivity. Doping G 6 HSPB into the Nafion matrix prepared composite membranes for testing the performance of fuel cells. At 80 °C and 98% RH, the proton conductivity of 9%-G 6 HSPB@Nafion reached a maximum value of 1.14 × 10 –1 S cm –1, which is 2.8 times higher than recast Nafion. The results showed that charge-assisted HOFs with high proton channel density have better proton transport properties, providing a reference for the design of highly proton-conducting materials.