Hierarchical Design of Mn₂P Nanoparticles Embedded in N,P-Codoped Porous Carbon Nanosheets Enables Highly Durable Lithium Storage

Abstract

Although transition metal phosphide anodes possess high theoretical capacities, their inferior electronic conductivities and drastic volume variations during cycling lead to poor rate capability and rapid capacity fading. To simultaneously overcome these issues, we report a hierarchical heterostructure consisting of isolated Mn2P nanoparticles embedded into nitrogen- and phosphorus-codoped porous carbon nanosheets (denoted as Mn2P@NPC) as a viable anode for lithium-ion batteries (LIBs). The resulting Mn2P@NPC design manifests outstanding electrochemical performances, namely, high reversible capacity (598 mA h g-1 after 300 cycles at 0.1 A g-1 ), exceptional rate capability (347 mA h g–1 at 4 A g–1), and excellent cycling stability (99% capacity retention at 4 A g–1 after 2000 cycles). The robust structure stability of Mn2P@NPC electrode during cycling has been revealed by the in situ and ex situ transmission electron microscopy (TEM) characterizations, giving rise to long-term cyclability. Using in situ selected area electron diffraction and ex situ high-resolution TEM studies, we have unraveled the dominant lithium storage mechanism and confirmed that the superior lithium storage performance of Mn2P@NPC originated from the reversible conversion reaction. Furthermore, the prelithiated Mn2P@NPC∥LiFePO4 full cell exhibits impressive rate capability and cycling stability. This work introduces the potential for engineering high-performance anodes for next-generation high-energy-density LIBs.

A Self‐Healing Volume Variation Three‐Dimensional Continuous Bulk Porous Bismuth for Ultrafast Sodium Storage

“…To directly reveal the excellent structure stability of the 3DPBi electrode, the in situ TEM observation was performed in real time through the nanobattery shown in Figure 5a. [30,[50][51][52][53][54] The 3DPBi is attached to the gold (Au) probe, and Na/Na 2 O is sticked to the tungsten (W) probe tip, where the as-formed Na 2 O on Na acts as a solid electrolyte. [30] The 3DPBi is sodiated when a negative bias (−7 V) is applied to the W probe.…”

“…To get insight into the phase transformation process of the 3DPBi anode during the sodiation/desodiation process, in situ SAED and ex situ XRD are performed (Figure 5i-k and Figure S17, Supporting Information). [5,21,50] The SAED pattern changes significantly during the alloying process, shown in Movie S3, Supporting Information. The distinct diffraction pattern changes of the 3DPBi during sodiation process are captured by the time-resolved images in Figure 5i-k (captured from Movie S3, Supporting Information).…”

A chain-like compound of Si@CNT nanostructures and MOF-derived porous carbon as an anode for Li-ion batteries

“…Affected by global environmental degradation and increasing energy demand (especially in electric vehicles and the consumer electronics market), performing studies on the development of new energy storage devices has become more urgent [1][2][3][4]. Li-ion batteries (LIBs) are particularly attractive as energy storage devices on the basis of their high capacity density and longevity life [5][6][7][8].…”

Practical development and challenges of garnet-structured Li7La3Zr2O12 electrolytes for all-solid-state lithium-ion batteries: A review

“…Unfortunately, all of these energy conversion technologies require effective and convenient energy storage systems for their further applications. Therefore, innovative electrochemical energy storage technologies, such as Li-ion batteries (LIBs), Na-ion batteries, and supercapacitors, have been proposed to address this need [1][2][3][4][5][6][7][8]. LIBs are the most commonly used electrochemical energy storage devices available in the market today; these batteries play an indispensable role in daily life and are widely used in portable products, electric vehicles (EVs), and grid-scale energy storage systems [9][10][11][12][13][14][15].…”