A novel satellite-like structure of metal nanocrystals decorated on silicon@carbon core–shell nanoparticles achieves boosting of the initial coulombic efficiency.

Nitrogen-doped coral-like porous carbon embedded with small alloy nanoparticles was synthesized by a direct surfactant co-assembly approach and demonstrated excellent nitrate electrocatalysis ability.

Copper sulfide has been regarded as a promising thermoelectric material with relatively high thermoelectric performance and abundant resource. Large-scale synthesis and low-cost production of high-performance thermoelectric materials are keys to widespread application of thermoelectric technology. Here, Cu2–x S particles encapsulated in a thin carbon shell are fabricated by a scalable wet chemical method (19.7 g/batch). The synthesized particles go through the crystal-phase transition from orthorhombic to tetragonal during high-temperature annealing and sintering. After the phase transition, electrical conductivity of this composite (Cu2–x S@C) increases by approximately 50% compared to that of the pure Cu2–x S sample, and can be attibuted to an increase in carrier concentration. Phonon scattering interface formation and superionic phase of Cu2–x S@C results in very low lattice thermal conductivity of 0.22 W m–1 K–1, and maximum thermoelectric figure of merit (ZT) of 1.04 at 773 K, which is excellent for thermoelectric performance in pure-phase copper sulfide produced via chemical synthesis. This discovery sets the stage for the use of facile wet chemical synthesis methods for large-scale transition-metal chalcogenide thermoelectric material production.

Semiconducting metal oxides with abundant active sites are regarded as promising candidates for environmental monitoring and breath analysis because of their excellent gas sensing performance and stability. Herein, mesoporous WO 3 nanofibers with a crystalline framework and uniform pore size is successfully synthesized in an aqueous phase using an electrospinning method, with ammonium metatungstate as the tungsten sources, and SiO 2 nanoparticles and polyvinylpyrrolidone as the sacrificial templates. The obtained mesoporous WO 3 nanofibers exhibit a controllable pore size of 26.3–42.2 nm, specific surface area of 24.1–34.4 m 2 g −1 , and a pore volume of 0.15–0.24 cm 3 g −1 . This unique hierarchical structure, with uniform mesopores and interconnected channels, could facilitate the diffusion and transportation of gas molecules in the framework. Gas sensors, based on mesoporous WO 3 nanofibers, exhibit an excellent performance in acetone sensing with a low limit of detection (<1 ppm), short response-recovery time (24 s/27 s), a linear relationship in a broad range, and good selectivity.

In this study, the sintering behaviors of a series of mesoporous silica (FDU‐12, SBA‐15, MCM‐41, and mesoporous silica nanoparticles) and microporous zeolite (ZSM‐5) using spark plasma sintering (SPS) technology were investigated. Highly transparent glass was prepared at a low temperature from all the powders. In particular, FDU‐12 type of mesoporous silica could be fully densified at an ultralow sintering temperature (910°C). It is suggested that the collapse of ordered mesostructures during SPS process dependents on the large pore size/pore wall thickness ratio, appropriate pore arrangement and amorphous frameworks of mesoporous silica, which implies that the enhancement in sinterability is possibly derived from the in situ collapse of ordered mesostructures. Such present findings pave a new way toward the construction of functional dense bulk materials from mesoporous powders.

Mn2+ activated glass‐ceramic (GC) has received tremendous attention in the exploration of luminescent materials for solid‐state lighting due to the high stability, broad red emission, and low toxicity. However, the doped Mn2+ ions still suffer from the oxidation and uncontrollable ions migration during the melting process of conventional preparation techniques, which is detrimental to the luminescence performance. Herein, transparent Mn2+‐doped mullite GCs have been prepared at low temperature (∼850°C) via the spark plasma sintering of EMT‐type zeolite. The GC samples show typical red emission peaking at 620 nm that can be assigned to spin‐forbidden 4T1(G)→6A1(S) transition of Mn2+ located in the octahedral coordination site of the host. Owing to the charge compensation mechanism and produced oxygen vacancies, the self‐reduction of Mn3+ to Mn2+ ions is realized and the oxidization is inhibited. The mullite nanocrystals acted as additional scattering centers introduce Rayleigh scattering to enhance the emission intensity. Moreover, benefitted from the established mullite nanocrystals network, the Mn2+‐doped GCs exhibit improved thermal conductivity up to 1.79 W K−1 m−1 and more excellent mechanical properties than conventional GCs, simultaneously.

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