Pseudocapacitance of MXene nanosheets for high-power sodium-ion hybrid capacitors
نویسندگان
چکیده
High-power Na-ion batteries have tremendous potential in various large-scale applications. However, conventional charge storage through ion intercalation or double-layer formation cannot satisfy the requirements of such applications owing to the slow kinetics of ion intercalation and the small capacitance of the double layer. The present work demonstrates that the pseudocapacitance of the nanosheet compound MXene Ti2C achieves a higher specific capacity relative to double-layer capacitor electrodes and a higher rate capability relative to ion intercalation electrodes. By utilizing the pseudocapacitance as a negative electrode, the prototype Na-ion full cell consisting of an alluaudite Na2Fe2(SO4)3 positive electrode and an MXene Ti2C negative electrode operates at a relatively high voltage of 2.4 V and delivers 90 and 40 mAh g(-1) at 1.0 and 5.0 A g(-1) (based on the weight of the negative electrode), respectively, which are not attainable by conventional electrochemical energy storage systems.
منابع مشابه
Probing the electrochemical capacitance of MXene nanosheets for high-performance pseudocapacitors.
Pseudocapacitors, which can store more energy at high charge/discharge rates, have attracted considerable attention. The performance of a pseudocapacitive material mainly depends on the interaction between electrode materials and the electrolyte ions. However, the understanding of the interaction is still limited. Here, the performance of Ti2CT2 (T = O, F, and OH) nanosheets as pseudocapacitor ...
متن کاملArray of nanosheets render ultrafast and high-capacity Na-ion storage by tunable pseudocapacitance
Sodium-ion batteries are a potentially low-cost and safe alternative to the prevailing lithium-ion battery technology. However, it is a great challenge to achieve fast charging and high power density for most sodium-ion electrodes because of the sluggish sodiation kinetics. Here we demonstrate a high-capacity and high-rate sodium-ion anode based on ultrathin layered tin(II) sulfide nanostructur...
متن کاملTwo-Dimensional Vanadium Carbide (MXene) as Positive Electrode for Sodium-Ion Capacitors.
Ion capacitors store energy through intercalation of cations into an electrode at a faster rate than in batteries and within a larger potential window. These devices reach a higher energy density compared to electrochemical double layer capacitor. Li-ion capacitors are already produced commercially, but the development of Na-ion capacitors is hindered by lack of materials that would allow fast ...
متن کاملUltrathin Two-dimensional MXene Membrane for Pervaporation Desalination
As a new family of two-dimensional (2D) materials, MXene, with many attractive physicochemical properties, has attracted increasing attentions and been applied for various applications. Here, for the first time, ultrathin MXene membranes with thickness down to several tens of nanometers were developed for pervaporation desalination by stacking synthesized atomic-thin MXene nanosheets. Influence...
متن کاملOptimal Capacitor Allocation in Radial Distribution Networks for Annual Costs Minimization Using Hybrid PSO and Sequential Power Loss Index Based Method
In the most recent heuristic methods, the high potential buses for capacitor placement are initially identified and ranked using loss sensitivity factors (LSFs) or power loss index (PLI). These factors or indices help to reduce the search space of the optimization procedure, but they may not always indicate the appropriate placement of capacitors. This paper proposes an efficient approach for t...
متن کامل