One-step preparation of hierarchical porous carbons from poly(vinylidene chloride)-based block copolymers

A facile self-templating and activation-free method to fabricate the hierarchical porous carbons (HPCs) from poly(vinylidene chloride) (PVDC)-based block copolymers is reported in this article. A series of block copolymers consisted of PVDC and the polystyrene (PS) blocks were prepared via RAFT living radical polymerization. Effects of molar ratio between the PVDC and the PS blocks on the microphase separation and thermal degradation of the PVDC-b-PS copolymers, and the microstructure of the as-prepared porous carbons were investigated. The results show that the PVDC block acts as a good kind of carbon precursor capable of forming micropores (0.5-0.6 nm) due to the diffusion of small molecules eliminated during the degradation of the PVDC block, and the microdispersed PS block acts as a mesopore extender to generate the mesopores (3-30 nm) by the decomposition of the PS phase. The as-prepared HPCs have the unique structures with three-dimensionally interconnected micropores and mesopores. The high Brunauer-Emmett-Teller surface area (1220 m(2)/g) and total pore volume (0.92 cm(3)/g) were achieved through controlling the composition of block copolymer. The method is facile to prepare the HPCs and suitable to the PVDC-based copolymers with other pyrolyzable block.