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A hierarchical composite catalyst composed of a ZSM-5 coating on SiC nano-whiskers that grew on SiC foam supports was designed and synthesized to simultaneously improve the zeolite loading and mass transfer of both the reactants and products in the methanol-to-propylene (MTP) reaction. SiC nano-whiskers were first grown on SiC foam supports by a chemical vapor deposition method to construct a hierarchical porous structure on the struts. ZSM-5 type zeolite crystals with high coverage were then hydrothermally grown on the SiC nano-whiskers after their surface was properly modified with zeolite precursor gel. In this way, the mass loading of the zeolite coating and mass transfer property, the two key factors that hinder the catalytic properties of the ZSM-5/SiC foam composite reported in our previous work, were enhanced, which in turn substantially improved the stability and selectivity of the obtained ZSM-5/SiC nano-whisker/SiC foam composites in MTP reaction as compared with those of the ZSM-5/SiC foam composites and ZSM-5 pellets. [ABSTRACT FROM AUTHOR]

• Sandwich–like NiFe LDH/Co 1-x S heterostructure has been successfully prepared. • The 3D catalytic space provides extra active sites over the original NiFe LDH. • The lattice mismatch of NiFe LDH induces the formation of lattice strain in Co 1-x S. • The compressive strain possesses lower free energy in OER. • NiFe LDH/Co 1-x S exhibits excellent long–term durability after 150 h test. Sandwich–like NiFe layered double hydroxides/Co 1-x S (NiFe LDH/Co 1-x S) heterostructure with synergistic electrocatalytic effects for highly efficient oxygen evolution reaction is successfully prepared by electrodepositing Co 1-x S on the surface of NiFe LDH grown on nickel foam (NF). The NF supported heterostructure possesses three-dimensional (3D) catalytic space and strained heterointerface. Thereinto the Co 1-x S layer provides extra active sites over the original NiFe LDH. Besides, the lattice mismatch in the surface of NiFe LDH induces the formation of lattice strain in Co 1-x S, which thus modulates the local electronic structures. Density functional theory (DFT) calculations validate that the strained heterointerface has advantageous OER activity. From the results of electrochemical tests, the NiFe LDH/Co 1-x S possesses large number of active sites and fast charge transfer. More importantly, optimized structure and interface characteristics improve the electrocatalytic stability, resulting in long–term durability with almost no attenuation after 150 h constant current test. [ABSTRACT FROM AUTHOR]

Abstract Lithium‐sulfur batteries have stimulated great attention as an advanced power system for scale storage requirements due to the overwhelming energy density. However, the capacity degradation caused by polysulfide shuttle and volume expansion still impedes the practical application. Herein, we designed and fabricated a facile TiO 2 embedded sulfur bulks@MnO 2 nanosheets composite as scalable cathode for long-cyclic lithium-sulfur batteries. The TiO 2 nanoparticles were embedded in sulfur bulks, which played important roles in the coverage of the uniform MnO 2 nanosheets. The embedded TiO 2 sites and external MnO 2 nanosheets brought out the physic trapping and chemical synergistic encapsulation of polysulfides. Such a composite cathode exhibited high reversible capacity of 1289 mAh g−1 at 0.1 C and long-term cycling stability at high rate condition (430 mAh g‐1 after 500 cycles at 2 C). This work thus sheds new light on a scalable way to improve the electrochemical performance of sulfur cathode. Graphical abstract The TiO 2 embedded sulfur bulks@MnO 2 nanosheets (TSM) composite was fabricated through melting process followed by facile solution reaction. As a cathode for lithium-sulfur batteries, the embedded TiO 2 sites and external MnO 2 nanosheets in TSM composite brought out the physic trapping and chemical synergistic encapsulation of polysulfides. Thus, it exhibits long-term cycling stability at high rate condition (430 mAh g‐1 after 500 cycles at 2 C). fx1 Highlights • Scalable TiO 2 embedded sulfur bulks@MnO 2 nanosheets composite was fabricated. • TiO 2 sites in sulfur bulks play important role in the formation of MnO 2 nanosheets. • A synergistic encapsulation of polysulfides was achieved by combining TiO 2 with MnO 2. • The composite shows superior capacity and cyclic stability compared to S-TiO 2. [ABSTRACT FROM AUTHOR]