Biomimetic and flexible high-performance carbon paper prepared by welding three-dimensional carbon fiber network with polyphenylene sulfide spherical sites for fuel cell gas diffusion layer.

High-performance carbon fiber paper (CFP) is usually an important part of the fuel cell gas diffusion layer (GDL). However, the preparation of CFP for GDL is still a challenge due to its arduous preparation process. Here, inspired by the structure of bird's nest in nature, we present the original design of PPS spherical sites welding three-dimensional (3D) carbon fiber network to produce high-performance CFP by facile wet papermaking and heat treatment. With a 3D CF network as the skeleton and PPS spherical sites as the welding points, CFs/PPS composite paper exhibits good mechanical strength and outstanding flexibility. Meanwhile, the excellent conductivity (6.8 S/cm) is integrated with super-hydrophobic performance, electrothermal performance (T max = 365 °C), heat resistance (DTG max >575 °C), and corrosion resistance, becoming a high-performance multifunctional CFP. The mythical combination of these properties makes CFs/PPS composite paper an ideal candidate in the field of fuel cell GDL. In addition, the evolution of chemical structure of CF/PPS during carbonization is emphasized, which is of great significance for the properties of composite paper. This work presents a leap forward in the preparation of multi-property high-performance CFP in a simple method and is a key step toward exploring how the structural changes of CFs/PPS composite paper can be understood during carbonization. [Display omitted] • Inspired by the structure of bird's nest in nature. • High-performance carbon paper prepared without graphitization. • The fabulous multi-performance combination makes composite paper an ideal candidate for the fuel cell gas diffusion layer. [ABSTRACT FROM AUTHOR]