Developing highly efficient and stable non-Pt electrocatalysts for the oxygen reduction reaction (ORR) to replace the state-of-the-art noble metal is essential for commercialization of fuel cells. Fe-N-C-based electrocatalysts are considered as a promising alternative to commercial Pt/C. An efficient electrocatalyst commonly requires large density of active site, high surface area, and desirable porosity, especially multimodal porosity with both large pores for efficient mass transfer and small pores for exposing as many active sites as possible. Herein, a lamellar metal organic framework (MOF) was developed as a precursor to directly achieve such a highly active Fe-N-C electrocatalyst with high surface area and desirable bimodal porosity. The mesopores arising from the special lamellar morphology of MOF benefits efficient mass transfer, and the nanopores resulting from pyrolysis of the MOF makes the majority of active sites accessible to electrolyte and thus effective for ORR. Uniform distribution of active elements N, C, and Fe at the molecular level in MOF precursor ensures abundant well-dispersed highly active sites in the catalyst. As a result, the catalyst exhibited superior ORR electrocatalytic activity and stability to commercial Pt/C. This strategy, using rarely reported lamellar MOF to prepare ORR catalysts with the merits mentioned, could inspire the exploration of a wide range of electrocatalysts from lamellar MOF precursors for various applications.

Through the introduction of well-distributed tin oxide nanocrystals on the surface of pre-prepared TiO2 nanotubes and followed by carbon coating, a novel TiO2 / SnO2-C double-shells nanotube has been synthesized. As an anode material of Li-ion batteries (LIBs), DSNTs exhibit excellent long-term cycling stability (256.0 mAh·g −1 at 1 A·g −1 , negligible capacity decay after 710 cycles) and satisfactory rate capability, which are ascribed to the synergetic effects of a unique combination of material properties in the well-designed conductive matrix: high volume stable titanium dioxide to form one-dimensional (1D) core section to maintain the structures, large theoretical capacity tin oxide as functional layer to increase capacity and high conductive carbon as buffer layer to accelerate charging rate.

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