Hollow carbon architectures with mesoporous shells via self-sacrificial templating strategy using metal-organic frameworks

Abstract

A self-template method is reported to prepare hollow-structured and ordered mesoporous carbon (HOMC) nanoplates by depositing resol-F127 monomicelles onto the surface of metal-organic-framework nanosheets, followed by hydrothermal reaction and carbonization. From adding FeCl 3 during the hydrothermal reaction, Fe-doped HOMC can be obtained after carbonization, which exhibits higher electrocatalytic activity and efficiency than the commercial Pt/C during the oxygen reduction reaction • Hollow-structured OMC (HOMC) nanosheets are prepared by a self-template strategy. • Fe-doped HOMC is obtained as a result from adding FeCl 3 during assembly process. • The Fe-doped HOMC exhibits outstanding electrocatalytic ORR performance. The rational design and fabrication of ordered mesoporous materials with highly exposed surface area are of great significance to address the fundamental challenges in electrochemistry-related applications by providing more active sites and fast ion/gas diffusion channel. In this work, a self-template method is reported to prepare hollow-structured mesoporous carbon (HOMC) nanoplates by depositing resol-F127 micelles onto the surface of metal–organic-framework (MOF) nanoplates, followed by hydrothermal reaction and carbonization. The parameters influencing the morphology and microstructure of the HOMC materials, i.e. , the MOF-to-resol-F127 ratio and the concentration of resol-F127 micelles, are systematically investigated. Fe-doped HOMC (Fe/HOMC) is obtained after carbonization, as a result from adding FeCl 3 during the hydrothermal reaction. Benefiting from morphological aspects, such as the nanoplate shape, the hollow structure, and mesoporous walls, the Fe/HOMC exhibits higher electrocatalytic activity and efficiency than the commercial Pt/C during oxygen reduction reaction (ORR). In addition, when compared to traditional Pt/C benchmark, the Fe/HOMC shows a superior durability and tolerance to methanol poisoning while operating for ORR. The assembled Zn-air battery possesses high power densities with excellent cycling stability. The strategy proposed here can provide a new avenue for the design of ordered mesoporous materials with hollow structure for a wide variety of applications.