FeSb@N-doped carbon quantum dots anchored in 3D porous N-doped carbon with pseudocapacitance effect enabling fast and ultrastable potassium storage

FeSb2 Nanoparticles Embedded in 3D Porous Carbon Framework: An Robust Anode Material for Potassium Storage with Long Activation Process

“…Most of the observed particles in the carbon matrix are amorphous/nanocrystalline particles (Figure 4h) and the lattice fringes with widths of 0.213 nm and 0.300 nm observed in the HRTEM image (Figure 4i) may belong to the (121) plane of FeSb 2 and the (110) plane of K 3 Sb (PDF#04‐0643, PDF#19‐0935), respectively. [ 15,24 ] Besides, the FeSb 2 @3DPC samples after 200 and 300 cycles were also tested by XRD, and their profiles were basically similar to those of the samples cycled for 100 cycles (Figure S10, Supporting Information). Nevertheless, the (111) peak of the FeSb 2 located at about 34.8° is still able to be observed in the patterns of the 100th cycle, while it cannot be distinguished in the patterns of the 200th and 300th cycles, indicating that the FeSb 2 has reacted more completely with the further increase of the cycle number.…”

“…[ 14 ] After calcination in the N 2 atmosphere, the organic components in potassium citrate, sodium alginate, and potassium antimony tartrate were pyrolyzed into carbon materials, and in the meantime, Fe and Sb were reduced and alloyed to form FeSb 2 intermetallic compounds. [ 15 ] Benefited from the barrier of NaCl particles and the confinement of carbon materials, FeSb 2 particles could be firmly embedded in carbon materials and their sizes were expected to be limited to an ultra‐small scale. As the NaCl particles were dissolved and removed, a large number of voids inside the material emerged.…”

“…Moreover, the two peaks at 712.1 and 725.5 eV can be assigned to the responses of Fe(III) 2P 3/2 and Fe(III) 2P 1/2 , respectively, while the peaks at 719.7 and 732.5 eV are their respective satellite peaks. [15,22] Since only partial pore structure can be observed by SEM and TEM images, in order to analyze the effect of pore formation more comprehensively, the N 2 adsorption and desorption experiment was also carried out. The obtained N 2 isotherm adsorption and desorption curves are shown in Figure 2e, and the specific surface area of the FeSb 2 @3DPC calculated by the Brunauer-Emmett-Teller (BET) method is 381.3 m 2 g −1 .…”

“…Moreover, the two peaks at 712.1 and 725.5 eV can be assigned to the responses of Fe(III) 2P 3/2 and Fe(III) 2P 1/2 , respectively, while the peaks at 719.7 and 732.5 eV are their respective satellite peaks. [ 15,22 ]…”

Renewable Biomass Flax-Derived Amorphous Carbon@SnO2 with a Graphene Buffer Layer for Enhanced Li Storage Performance

“…Though transition metal oxides have been extensively studied as potential high-capacity anode materials for lithium-ion batteries, SnO 2 has garnered the most attention among them because of its high theoretical specific capacity of 782 mA h g –1 , low price, eco-friendliness, and high natural abundance . However, the SnO 2 -based anodes underwent a volume change of 200–300% during lithiation and de-lithiation. , Internal stresses resulting from large volume changes can lead to electrode cracking, high initial irreversible capacity, and finally leading to a rapid capacity decay. − …”