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Among the alloying‐type anodes, elemental Sb possesses the suitable yet safe plateau, simple lithiation pathway, small voltage polarization, high conductivity, and superior cycle stability. However, challenge is that its intrinsic capacity is rather low (660 mAh g−1), <1/6 of silicon. Herein, we propose a seamless integration strategy by merging the voltage and capacity of phosphorus and antimony into a solid solution alloy. Interestingly, the enlistment of P is found greatly enlarge the capacity from 660 to 993 mAh g−1 for such Sb30P30 solid solution, while maintaining a single and stable discharge plateau (~0.79 V) similar to elemental Sb. Various experimental characterizations including XPS, PDF, Raman, and EDS mapping reveal that in such a material the P and Sb atoms have interacted with each other to form a homogenous solid solution alloy, rather than a simple mixing of the two substances. Thus, the Sb30P30 exhibits superior rate performances (807 mAh g−1 at 5000 mA g−1) and cyclability (821 mAh g−1 remained after 300 cycles). Furthermore, such Sb60‐xPx alloys can even deliver 621 mAh g−1 at −30°C, which can be served as the alternative anode materials for high‐energy and low‐temperature batteries. This unique seamless integration strategy based on solid solution chemistry can be easily leveraged to manipulate the capacity of other electrode materials at similar voltage. [ABSTRACT FROM AUTHOR]

The monoclinic GeP with large capacity, low plateau, and high initial coulombic efficiency (ICE) has been proved to be alternative anode for Li‐ion batteries. However, the heavy use of Ge raw material with its high price, hinders its further development. Herein, the Zn atom is proposed for substitution into GeP and replaces part of the Ge owing to its low price, suitable plateau, and similar radius. Interestingly, a novel Ge1−xZnxP solid solution with a wide range tunable region (0.143 < x < 0.6) is achieved, reducing the heavy use of Ge and cutting the GeP price down. More intriguingly, such Ge1−xZnxP possesses a new phase, different from monoclinic GeP, which is first verified to be a cubic system in F‐43m. Compared to semi‐conducting GeP, this cubic Ge1−xZnxP phase possesses metallic conductivity, thus enabling a better rate performance than monoclinic GeP (e.g., 881 vs 283 mAh g−1 at 2000 mA g−1), while keeping the great advantages of large capacity, low plateau, and high ICE of GeP as well. Consequently, the assembled LiCoO2//Ge1−xZnxP full cell exhibits large capacity over 1000 mAh g−1. This unique phase control strategy by atomic substitution can be easily extended to manipulate electrochemical behaviors of other multi‐phase materials toward advanced energy storage. [ABSTRACT FROM AUTHOR]

Defect engineering is an important approach to enhancing the catalytic activity of a material, but there have been few reported controllable experiments due to the lack of systematic and comprehensive understanding of the effects of defects. For nanocarbon catalysts, it is still a challenge to prepare both atom-doped and defect-engineered catalysts with the desired more effective active centers, which requires an in-depth understanding of both experiment and theory. Herein, a topological rich-vacancy-defect nitrogen-doped nanocarbon (TRNC) material is constructed in situ via a simple magnesiothermic technology. It exhibits remarkable oxygen catalytic performance, which can be compared to the best metal-free bifunctional carbon electrocatalysts reported, even better than that of commercial noble-metal RuO2. Combined with density functional theory (DFT) calculations, the carbon vacancy defects with edge nitrogen doping as intrinsic active sites were found to exhibit excellent oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity. When used practically as a catalyst in Li–O2 batteries, with a capacity restriction of 500 mA h g−1, it displays a long cycling and high rate durability of over 300 cycles at 200 mA g−1. This excellent performance arises from the three-dimensional topological rich-vacancy-defect nitrogen-doped nanocarbon. The effects of vacancy sites and nitrogen doping were probed via first-principles simulations to clarify the catalytic mechanisms which contribute to this superior performance. [ABSTRACT FROM AUTHOR]

Abstract: The metal sulfide or selenides have attracted increasing attention for high‐energy lithium‐ion batteries due to their unique layer structure flexibility, higher conductivity, and lower voltage polarization than metal oxides. However, low initial coulomb efficiency (ICE), serious structure destruction, and irreversible bonding chemistry are still big challenges for their practical application. Herein, layer GeSe2 and its carbon composite are synthesized by high‐energy ball milling and it is surprisingly found that crystalline c‐GeSe2 possesses higher reversible capacity and better rate performances than their amorphous counterparts. More specially, the broken GeSe bondings upon lithiation are also observed to regenerate after delithiation. These unusual phenomena are investigated by both experimental tools and theoretical calculations. Compared to other typical MX2 (M = Mo, W, X = S, Se), the electronegativity of Ge is more close to selenium and the formation energy of GeSe bonding is much smaller. Thus, a mild driven force such as thermoheating at low temperature can recover the ordered layer structure, helping to heal the high conductivity and unimpeded Li diffusion pathways for crystalline GeSe2. Similarly, electrochemical delithium force also triggers the rebuilding of GeSe bonding upon Li‐extraction, boosting GeSe2/C with large capacity (1050 mA h g−1), ultrahigh ICE (94%), and cycling stability. [ABSTRACT FROM AUTHOR]

Current electrode materials for commercial lithium ion batteries (LIBs) suffer from poor low temperature electrochemical performance, which seriously limits their application in winter and cold climate areas. Herein, pure phase LISICON structured Li3V2(PO4)3 (r-LVP) was successfully prepared and investigated for the first time as a low temperature cathode for LIBs. Benefiting from a fast ionic conductive structure and high structural stability, the r-LVP exhibits an outstanding high rate performance in a wide temperature range from 25 °C to −20 °C. Even at −30 °C, a discharge capacity of 90 mA h g−1 at 0.2C can be achieved, corresponding to 80% of the room temperature capacity. After 5000 cycles at a high rate of 10C, 84% of the initial capacity can be retained at −10 °C. Such a high rate capability and long cycle stability promise r-LVP could be a competitive candidate for low temperature LIBs. [ABSTRACT FROM AUTHOR]