Nano-phosphorus supported on biomass carbon by gas deposition as negative electrode material for potassium ion batteries

A graphene-like hollow sphere anode for lithium-ion batteries

We report a flash Joule heating method for the rapid preparation of graphene-like materials. The L-GHS exhibited a uniform diameter of 200 nm and an ideal specific surface area of 670 m2 g-1. Meanwhile, the specific capacity of L-GHS remained at 942 mA h g-1 after 600 cycles (1 A g-1), which shows excellent electrochemical performance.

Phosphorus/Phosphide-Based Materials for Alkali Metal-Ion Batteries

Phosphorus- and phosphide-based materials with remarkable physicochemical properties and low costs have attracted significant attention as the anodes of alkali metal (e.g., Li, Na, K, Mg, Ca)-ion batteries (AIBs). However, the low electrical conductivity and large volume expansion of these materials during electrochemical reactions inhibit their practical applications. To solve these problems, various promising solutions have been explored and utilized. In this review, the recent progress in AIBs using phosphorus- and phosphide-based materials is summarized. Thereafter, the in-depth working principles of diverse AIBs are discussed and predicted. Representative works with design concepts, construction approaches, engineering strategies, special functions, and electrochemical results are listed and discussed in detail. Finally, the existing challenges and issues are concluded and analyzed, and future perspectives and research directions are given. This review can provide new guidance for the future design and practical applications of phosphorus- and phosphide-based materials used in AIBs.

Prospects of Electrode Materials and Electrolytes for Practical Potassium-Based Batteries

Potassium-ion batteries (PIBs) have attracted tremendous attention because of their high energy density and low-cost. As such, much effort has focused on developing electrode materials and electrolytes for PIBs at the material levels. This review begins with an overview of the high-performance electrode materials and electrolytes, and then evaluates their prospects and challenges for practical PIBs to penetrate the market. The current status of PIBs for safe operation, energy density, power density, cyclability, and sustainability is discussed and future studies for electrode materials, electrolytes, and electrode-electrolyte interfaces are identified. It is anticipated that this review will motivate research and development to fill existing gaps for practical potassium-based full batteries so that they may be commercialized in the near future.

Functional thiophene-diketopyrrolopyrrole-based polymer derivatives as organic anode materials for lithium-ion batteries

In this study, four thiophene-diketopyrrolopyrrole-based (TDPP-based) polymer derivatives modified by different groups and alkyl chains were synthesized. The effects of various functional groups on the electrochemical properties of the polymers for application in lithium-ion batteries were compared, where the carbazole (C) and tert-butyl acetate (TA) groups improved the capacity performance of the polymer electrodes, while hexane (H) and fluorene (F) groups enhanced the cycle stability of the polymer electrodes. The P(C-TDPP-TA) polymer electrode, i.e., the TDPP-based polymer composed of carbazole and tert-butyl acetate groups, exhibited the best capacity performance among the four polymer electrodes, where its discharge specific capacity and capacity retention were up to 357 mA h g-1 and 82% and its energy density and power density were 213 W h kg-1 and 149 W kg-1 at 100 mA g-1 after 500 cycles, respectively. The P(F-TDPP-H) polymer electrode, i.e., the TDPP-based polymer composed of fluorene and hexane groups, possessed the best cycle stability and conductivity, where its capacity retention was up to 92% at 100 mA g-1 for 500 cycles and its electronic conductivity and ionic conductivity were 4.80 × 10-3 and 6.68 × 10-3 S m-1, respectively. For application in lithium-ion batteries, the P(C-TDPP-TA) electrode exhibited the best comprehensive performance. When the current density reached up to 1000 mA g-1, after 1000 cycles, the P(C-TDPP-TA) electrode still exhibited a high discharge specific capacity (203.6 mA h g-1) and excellent capacity retention (88.8%), and its energy density and power density were 116 W h kg-1 and 376 W kg-1 (1000 mA g-1, after 1000 cycles), respectively. Therefore, the P(C-TDPP-TA) electrode has potential as a promising anode material for lithium-ion batteries.

Fe nanopowder-assisted fabrication of FeOx/porous carbon for boosting potassium-ion storage performance

The electrode materials of potassium ion storage system have attracted considerable attention given the promising prospect of a potassium ion system in large-scale electrochemical energy storage applications. Despite the excellent anode performance of metal oxides in Li⁺ and Na⁺ batteries, the study on their K⁺ storage performance is still rarely reported. In this study, we report a safe and low-cost strategy to prepare FeO_x/N-doped carbons by using NaHCO₃ and Fe nanopowder. Benefiting from the oxidation of Fe to Fe₃O₄, an interesting "one stone, two birds" role of the Fe powder can be identified in the heating process. As a reduction agent, the Fe powder can consume the excess oxygen in the bio-massed carbon framework, facilitating the formation of short-range-ordered domains in the biomass-derived carbon materials (FeO_x@GBHCs). Moreover, the close combination of oxidization products (Fe₃O₄ particles) and carbon matrix leads to numerous FeO_x clusters grafted on the surface of the carbon framework via the strong C-O-Fe binding. Therefore, the resultant FeO_x/porous carbon exhibits a high reversible capacity of 410 mA h g^-1 and an excellent cycling capability. The assembled FeO_x@GBHCs//AC potassium-ion hybrid supercapacitor delivers a high energy density of 133 W h kg^-1 at a power density of 700 W kg^-1, demonstrating a potential prospect of metal oxides in boosting the potassium ion storage performance.