An insight into the initial Coulombic efficiency of carbon-based anode materials for potassium-ion batteries

https://onlinelibrary.wiley.com/doi/pdf/10.1002/aenm.202100856

Perspective on Carbon Anode Materials for K+ Storage: Balancing the Intercalation-Controlled and Surface-Driven Behavior

Heteroatom doping effectively tunes the electronic conductivity of transition metal selenides (TMSs) with rapid K+ accessibility in potassium ion batteries (PIBs). Although considerable efforts are dedicated to investigating the relationship between the doping strategy and the resulting electrochemistry, the doping mechanisms, especially in view of the ion and electronic diffusion kinetics upon cycling, are seldom elucidated systematically. Herein, the crystal structure stability, charge/ion state, and bandgap of the active materials are found to be precisely modulated by favorable heteroatom doping, resulting in intrinsically fast kinetics of the electrode materials. Based on the combined mechanisms of intercalation and conversion reactions, electron and K+ ion transfer in Ni‐doped CoSe2 embedded in carbon nanocomposites (Ni‐CoSe2@NC) can be significantly enhanced via electronic engineering. Benefiting from the synthetic controlled Ni grains, the heterointerface formed by the intermediate products of electrochemical reactions in Ni‐CoSe2@NC strengthens the conversion kinetics and interdiffusion process, developing a low‐barrier mesophase with optimized potassium storage. Overall, an electronic tuning strategy can offer deeper atomic insights into the conversion reaction of TMSs in PIBs.

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/advs.202200341

Doping‐Induced Electronic/Ionic Engineering to Optimize the Redox Kinetics for Potassium Storage: A Case Study of Ni‐Doped CoSe2

Microwave-assisted synthesis of carbon dots modified graphene for full carbon-based potassium ion capacitors

Recently, the limited abundance and uneven geographical distribution of Li resources seriously hamper the growing demand for lithium-based energy storage devices. In this regard, potassium-ion batteries (KIBs) sharing similar “rocking chair” working principles with lithium-ion batteries have started to attract increasing attention due to their high energy density and abundant potassium resources. Carbon material is considered to show great potential for using as high-performance anode in KIBs. However, it is still a challenge to simultaneously achieve satisfactory specific gravimetric and volumetric capacities, high initial Coulombic efficiency, superior rate performance, and excellent cycle stability due to the sluggish reaction kinetics of the large-sized K-ions. Herein, we summarize the latest research achievements of different types of carbon anodes for KIBs, including graphite, graphene, hard carbon, soft carbon, and carbon nanotubes, in which the key factors affecting the electrochemical performance are explored. Importantly, the alternative strategies for addressing the low gravimetric/volumetric capacity and low initial Coulombic efficiency of carbons are thoroughly emphasized. Finally, the critical issues, challenges, and perspectives are proposed to show the development direction of KIBs. We hope this review can provide researchers with new ideas to design high-performance carbon materials and give insightful perspectives to accelerate the application of carbon electrodes for KIBs. The latest research achievements of different types of carbon anodes for KIBs are summarized, including graphite, graphene, hard carbon, soft carbon, and carbon nanotubes, in which the key factors affecting the electrochemical performance are demonstrated. Importantly, the alternative strategies for addressing the low gravimetric/volumetric capacity and low initial Coulombic efficiency of carbons are thoroughly emphasized. Finally, the critical issues, challenges, and perspectives are proposed to show the development direction of KIBs. • The latest progress of carbon materials in potassium ion batteries are presented. • Promising strategies to improve the potassium storage performances are emphasized. • Challenges and prospects for the future development of carbon materials are highlighted. 

Designing Carbon Anodes for Advanced Potassium-Ion Batteries: Materials, Modifications, and Mechanisms

https://onlinelibrary.wiley.com/doi/pdf/10.1002/adfm.202004348

Toward High-Performance Capacitive Potassium-Ion Storage: A Superior Anode Material from Silicon Carbide-Derived Carbon with a Well-Developed Pore Structure

Xiaxiang Zhang

Papers

Toward High-Performance Capacitive Potassium-Ion Storage: A Superior Anode Material from Silicon Carbide-Derived Carbon with a Well-Developed Pore Structure