(177f) Universal Doping Strategy for Ordered Mesoporous Carbons Towards High Performance Energy Storage

Heteroatom-doped porous carbons provide desirable characteristics for energy storage applications, such as fuel cells, batteries or supercapacitors. Challenges with these materials generally involve poor control of the pore size, limitation in the doping extent, and scalability of the production process. Self-assembly with block copolymer templates provides the great opportunity for precise control of their pore characteristics, but the conventional processes still suffer from low batch production (<100mg) and limited doping concertation (< 15 at%) in the final carbon framework. Here, we will demonstrate a large-scale fabrication (> kg) methodology for a wide variety of functional mesoporous materials through a continuous roll-to-roll processing, which is compatible with the traditional evaporation-induced self-assembly process. The ability to generate large quantities of materials has enabled a new and universal material doping strategy through a simple modification of calcination process. Infiltration of molten dopants into a silica reinforced mesoporous crosslinked polymer provides a precursor material that on carbonization yields high heteroatom content (up to 40 at%) of various elements (nitrogen, sulfur, phosphorous and boron). The composition of the resultant mesoporous carbons can be controlled with appropriate selection of heteroatom precursor and its mass loading. We will also discuss about how to design an ultra-long cycle life, low-cost Na-S battery using these doped carbons. The introduction of high concentration heteroatoms effectively traps sulfurs to minimize polysulfide dissolution/shuttling through strong Na-N bonds and electrostatic interactions between doped carbon surface and polar sulfides.