Amorphous Se Restrained by Biomass-Derived Defective Carbon for Stable Na–Se Batteries

Abstract

Rechargeable sodium–selenium (Na–Se) batteries have attracted increasing attention due to their high energy density and the abundant resource of Na. However, their practical application is hindered by a short lifespan due to the active material dissolution, shuttling effect, and volume variation of the Se cathode. Herein, we report a facile strategy to significantly boost the cycling stability of the Se cathode by restrained amorphous Se into a N/O-doped defective carbon matrix derived from poplar-catkin (Se@NOPCC). Density functional theory calculations and experimental results elucidate that N/O active sites on the defective carbon enable a strong chemical affinity with the Se chain and NaSe2/Na2Se discharged products, which suppresses the shuttling effect and dissolution issues. In addition, the amorphous Se embedded in the hierarchically porous carbon relieves the strain and accommodates the huge volume variation during the sodiation/desodiation process. Consequently, the designed Se@NOPCC cathode exhibits a remarkable reversible capacity of 646 mAh g–1 at 0.05 A g–1 and a long cycling life with 83.8% capacity retention over 1600 cycles at 1.0 A g–1. This work offers a possibility for building stable Na–Se batteries and will also encourage more investigations on the combination of energy application and biomass materials.

Surface-driven fast sodium storage enabled by Se-doped honeycomb-like macroporous carbon

“…After discharge to 0.01 V, the Se 3d peak visibly shifts toward low binding energy, and a new peak located at 54.3 eV appears, which can be attributed to the formation of Na x Se. 18,20 This result confirms that the doped Se atoms supply additional Na storage sites through redox reactions, leading to the high capacity of the Se-HMC electrodes.…”

“…18,19 In recent years, several high-capacity Na-Se batteries have been reported based on this electrochemical redox reaction mechanism. 20,21 In addition, Se-doping has been proven to be able to change the state of electron distribution and subsequently improve the electrical conductivity of target materials. [22][23][24][25] Moreover, the atomic size of Se is very large (40.2 nm in diameter), so the introduction of the Se element can effectively expand the interlayer distance of carbon to improve the diffusion kinetics of Na + .…”

Highly efficient sulfur cathode built from biomass of hierarchical porous carbon for aqueous Cu–S batteries

“…The XRD pattern of S@NHPC was found to be clearly different from that of NHPC, and showed sharp peaks assignable to the diffraction lines of S, hence indicating the presence of sulfur and consistent with the discussion of the SEM and HRTEM results. 37 Nitrogen adsorption-desorption isotherms, shown in Fig. 2b, unveiled a disordered porous structure of NHPC with a specific surface area of 1167.16 m 2 g −1 and a pore volume of 0.21 cm 3 g −1 -but, for S@NHPC, a much lower specific surface area of only 2.5943 m 2 g −1 and a pore volume of 0 cm 3 g −1 , suggesting a high loading of sulfur in the pores of NHPC.…”

Facile aqueous synthesis of hollow dual plasmonic hetero-nanostructures with tunable optical responses through nanoscale Kirkendall effects

“…40 However, the studies on the compositional and structural diversity of such hollow dual plasmonic nanoparticles are still largely underdeveloped since all reports published so far are only focused on Au@Cu 2-x S. 7,29,[41][42][43] To the best of our knowledge, synthesis and characterization of hollow dual plasmonic Au@Cu 2-x Se hybrid nanostructures have not been reported yet, albeit very scarce synthetic protocols published for bare hollow copper selenide nanoparticles. 44,45 In light of the important applications of selenium-containing nanoparticles nowadays in energy storage 46,47 and cancer treatment, 48,49 it is fundamentally and technologically imperative to develop a deeper understanding of the design and synthesis of such nanostructures with deliberately controlled morphologies, compositions, and surface architectures.…”