Coupling hierarchical iron cobalt selenide arrays with N-doped carbon as advanced anodes for sodium ion storage

Abstract

Transition metal selenides have emerged as a class of promising anodes for sodium ion batteries (SIBs). However, the notorious issues of their unsatisfied electrical conductivity and huge volume changes during...

A gradient hexagonal-prism Fe3Se4@SiO2@C configuration as a highly reversible sodium conversion anode

“…6c deliver initial charge and discharge capacities of 1001 and 506 mA h g À1 , respectively (based on the anodic mass), with an ICE of only 50.2% at 1.0 A g À1 , where the low ICE of the full cell is probably due to the loss of active Na + in the electrolyte expended during the fabrication of the SEI lm. 75 Aer experiencing 100 cycles of the Na + movement at 1.0 A g À1 (Fig. 6d), a high specic capacity of the full cell is maintained at 241 mA h g À1 .…”

“…30,31 However, as a prevalent issue shared by the other TMS-based anodes, the developed iron selenides are subject to various physicochemical changes in continual deintercalation and conversion processes, involving structural variation, phase transformation, and electrochemical reorganization. These not only induce high internal severe deterioration of the electrode followed by rapid fading of the reversible capacity, 32 but also result in the consecutive fabrication of an unstable solid electrode interface (SEI) lm and thus in dissatisfactory rate performance. 33 The inferior electronic conductibility inevitably results in sluggish reaction kinetics as well, which restricts their further application.…”

Cu-Based Multicomponent Metallic Compound Materials as Electrocatalyst for Water Splitting

“…The multiple peaks at 713.2, 725.2, 711.0, and 713.1 eV can be assigned to the Fe 3+ 2p 1/2 , Fe 3+ 2p 3/2 , Fe 2+ 2p 1/2 , and Fe 2+ 2p 3/2 , while the shake-up satellite peaks are observed at 718.3 and 733.9 eV ( Ge et al, 2018 ). The high-resolution Co 2p spectrum ( Figure 2C ) displays two major peaks at 781.4 and 797.1 eV, corresponding to Co 2p 3/2 and Co 2p 1/2 , respectively ( Wang et al, 2021 ; Tabassum et al, 2019 ). The Ni 2p XPS spectra can be fitted to four components located at 855.9 and 873.5 eV corresponding to Ni 2p 3/2 and Ni 2p 1/2 , as shown in Figure 2D ( Wu et al, 2017 ).…”

Bimetallic Copper Tin Sulfide Nanosheet Arrays Encapsulated in Nitrogen-Doped Carbon Shells for Boosted Sodium Storage Performance

“…Figure D depicts the C 1s spectrum consisting of four deconvoluted peaks, which contains different C bonds including sp 2 -hydridized carbon (C–C/CC) (284.5 eV), C–N (285.6 eV), C–S (286.2 eV), and CO (288.4 eV) . Regarding the spectrum of N 1s, three major fitted peaks can be observed at 398.4, 399.8, and 400.6 eV (Figure S4B), which are assigned to the pyridinic-N, pyrrolic-N, and graphitic-N, respectively, and the N content is measured to be 6.9 at. % by XPS analysis.…”