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Bimetallic alloy nanomaterials are promising anode materials for potassium‐ion batteries (KIBs) due to their high electrochemical performance. The most well‐adopted fabrication method for bimetallic alloy nanomaterials is tube furnace annealing (TFA) synthesis, which can hardly satisfy the trade‐off among granularity, dispersity and grain coarsening due to mutual constraints. Herein, we report a facile, scalable and ultrafast high‐temperature radiation (HTR) method for the fabrication of a library of ultrafine bimetallic alloys with narrow size distribution (≈10–20 nm), uniform dispersion and high loading. The metal‐anchor containing heteroatoms (i.e. O and N), ultrarapid heating/cooling rate (≈103 K s−1) and super‐short heating duration (several seconds) synergistically contribute to the successful synthesis of small‐sized alloy anodes. As a proof‐of‐concept demonstration, the as‐prepared BiSb‐HTR anode shows ultrahigh stability indicated by negligible degradation after 800 cycles. The in situ X‐ray diffraction reveals the K+ storage mechanism of BiSb‐HTR. This study can shed light on the new, rapid and scalable nanomanufacturing of high‐quality bimetallic alloys toward extended applications of energy storage, energy conversion and electrocatalysis. [ABSTRACT FROM AUTHOR]

Electrode dissolution/collapses and interfacial reactions pose challenges to batteries, leading to pronounced capacity loss particularly during the initial few cycles. As high‐capacity conversion/alloying anodes for sodium storage, metal sulfides generally show unsatisfactory performances like poor initial Coulombic efficiency (ICE; mostly <70% in the usual electrolyte) and inferior cyclic stability due to thick solid‐electrolyte interface (SEI) layer formation and ubiquitous volume/phase changes. Using SnS2 as an example, here, sulfides are elaborately encapsulated into functionalized amorphous tridymite/carbon reactors to address the above issues. The outer tridymite/carbon manifests good ionic permeability and superb electrochemical/mechanical tolerance against destructive Na+ insertion. Confining actives into tailored reactors endows SnS2 full of nanoboundaries with an ultrahigh ICE of ≈89.13% and remarkable electrochemical attributes including large initial capacity (Max. 733.24 mAh g−1), prominent stability in subsequent cycles, and excellent rate capability. Detailed investigation unveils that thin and steady SEI condition on tridymite/carbon rather than SnS2 is key to achieving outstanding ICE. Engineered reactors always keep intact and free of valence‐state changes, guaranteeing capacities running at a high level without an evident downtrend. Their peculiar functions on enlisting Na+ diffusion/transport and inhibiting sulfides' release are also discussed. Packed full‐cell Na‐ion batteries with less irreversibility may show great potential in practical utilizations. [ABSTRACT FROM AUTHOR]

Aiming to the repetitively large volume change and the inevitably loss of volumetric capacity of bismuth (Bi) based sodium-ion battery (SIB) during cycling, a binder-free Bi anode based on one-step electrochemical co-deposited three-dimensional Bi nanosheets and conductive carbon nanotube networks (Bi NS/CNTs) was developed. Compared with the sole Bi anode achieved via the same strategy, the co-deposition of 3D hierarchical Bi nanosheet/CNTs arrays manifests the strong interfacial adhesion and accommodates the volume change upon sodium alloying/dealloying. Such structural feature endows the Bi NS/CNTs anode a long-term cycling stability (383.72 mAh g−1 at 0.1 A g−1 after 200 cycles, 311.68 mAh g−1 at 1 A g−1 after 1000 cycles) and a good rate performance. A full SIB assembled with Bi NS/CNTs anode and Na 3 (VOPO 4) 2 F@rGO cathode shows a high operating voltage (above 4 V) and a high energy density of 221.99 Wh kg−1, which outperforms many reported Bi-based analogues. This work may open a new opportunity for developing efficient SIB with high energy and good practicability. [Display omitted] • Binder-free 3D Bi NS/CNTs arrays anode was built via electrochemical co-deposition. • 3D hierarchy manifests strong interfacial adhesion and accommodates volume change. • Excellent cycling stability and rate capability are achieved. • NVOPF@rGO//Bi NS/CNTs full cell shows high operating voltage and energy density. [ABSTRACT FROM AUTHOR]

• SiO x /C@void@C yolk-shell structure was synthesized via a facile template strategy. • N, S co-doping improves electrical conductivity and generates defects/active sites. • Yolk-shell structure can effectively buffer large volume change during cycling. • SiO x /C@void@C anode exhibits excellent electrochemical performance in LIB. [Display omitted] Silicon oxide (SiO x) is an attractive anode material for lithium-ion battery due to its high specific capacity and low working potential. However, its scale utilization confronts with low electrical conductivity and large volume expansion. Herein, a yolk-shell structured N, S co-doped SiO x /C@void@C nanosphere is fabricated through a one-pot organosilica template mediated strategy. The co-doping of N, S enables SiO x /C@void@C with good conductivity, increased lithium storage capacity and improved interfacial contact. The hollow void between SiO x /C core and carbon shell effectively buffers the large volume change during the cycling. Consequently, the yolk-shell SiO x /C@void@C structures exhibit excellent electrochemical performance, with a high discharge specific capacity of 879 mAh·g−1 after 100 cycles at 0.1 A·g−1, outstanding rate capability of 464 mAh·g−1 at 5 A·g−1 and excellent cycling stability of 584 mAh·g−1 after 500 cycles at 1.0 A·g−1. [ABSTRACT FROM AUTHOR]