Recent advances of 3D compressible carbon assemblies: A review of synthesis, properties and applications in energy and environment

Three-dimensional (3D) compressible and elastic carbon materials, by virtue of lightweight, high electrical conductivity, excellent mechanical properties and thermal stability, high adsorption capacity and distinguished environmental compatibility, are attracting expanding attention and showing great promising applications in scientific and engineering fields, especially in flexible and wearable electronics. Herein, this review summaries the latest progress of 3D carbon compressible assemblies on the synthesis, properties and applications of carbon nanotubes and nanofiber sponges, graphene aerogels, biomass and synthetic polymer sponges. This paper also describes the relationship between the structural characteristics and properties, in terms of the introduction of heteroatoms, polymers, transition metal oxides/sulfides or other guests to improve the electrochemical properties of 3D carbon sponges. Furthermore, their applications in sensing, energy storage and conversion, environmental protection, thermal insulation and catalysis are discussed. Despite a number of diverse applications, a brief prospective on the challenges and outlooks are proposed.