Zinc‐Assisted Cobalt Ditelluride Polyhedra Inducing Lattice Strain to Endow Efficient Adsorption‐Catalysis for High‐Energy Lithium–Sulfur Batteries

Abstract

Developing a conductive catalyst with high catalytic activity is considered to be an effective strategy for improving cathode kinetics of lithium–sulfur batteries, especially at large current density and with lean electrolytes. Lattice‐strain engineering has been a strategy to tune the local structure of catalysts and to help understand the structure–activity relationship between strain and catalyst performance. Here, Co0.9Zn0.1Te2@NC is constructed after zinc atoms are uniformly doped into the CoTe2 lattice. The experimental/theoretical results indicate that a change of the coordination environment for the cobalt atom by the lattice strain modulates the d‐band center with more electrons occupied in antibonding orbitals, thus balancing the adsorption of polysulfides and the intrinsic catalytic effect, thereby activating the intrinsic activity of the catalyst. Benefiting from the merits, with only 4 wt% dosages of catalyst in the cathode, an initial discharge capacity of 1030 mAh g−1 can be achieved at 1 C and stable cycling performances are achieved for 1500/2500 cycles at 1 C/2 C. Upon sulfur loading of 7.7 mg cm−2, the areal capacity can reach 12.8 mAh cm−2. This work provides a guiding methodology for the design of catalytic materials and refinement of adsorption‐catalysis strategies for the rational design of cathode in lithium–sulfur batteries.

d-p Hybridization-Induced “Trapping–Coupling–Conversion” Enables High-Efficiency Nb Single-Atom Catalysis for Li–S Batteries

“…To reveal the merit of the S@Nb–SAs@NC cathode, the prolonged cycling stability is further evaluated at 2 C (Figure S25) and 4 C (Figure d). The corresponding charging/discharging profile of the Nb–SAs@NC catalyst (Figure S25a), in which a main reaction platform in the discharging curves is still kept after 600 cycles, reveals that the redox reaction of the sulfur cathode is well maintained with the increased cycles. − A reversible capacity of 807.4 mA h g –1 at 2 C corresponding to the capacity retention of 87.1% is obtained over 600 cycles (Figure S25b). Notably, the S@Nb–SAs@NC-based cell still delivers a high capacity of 692.6 mA h g –1 with an average 0.015% decay per cycle after 1000 cycles at 4 C, which is comparable with the state-of-the-art cathodes (Table S4).…”

Field‐assisted electrocatalysts spark sulfur redox kinetics: From fundamentals to applications

“…Third, a more general strategy by incorporating defect or doping has been widely adopted for the synthesis of electrocatalysts and proven to play an effective role in the enhancement of sulfur electrocatalytic activity. [ 94,175,180,187 ] To this end, Zhang et al explicated the appropriate energy level configuration of exposed orbitals for strengthened TM‐S covalency (Figure 7D) while our group rooted in asymmetric coordination engineering to activate horizontal d orbitals (Figure 7E), [ 94,175 ] both enabling superior LiPSs adsorption compared to the undoped structure in a preconceived manner. Notably, now that a different degree of localization for s, p, d, and f orbitals is acknowledged by the public, engineering gradient orbital coupling is shining in the near future.…”

“…[93,103,111] Beneficial from the versatile strategies (e.g., external force, defect, and lattice mismatch) for the introduction of strain in electrocatalysts, which is in response to flexible manipulation of tensile/ compressive strain, strain engineering flourishes in the exploration of SF-assisted electrocatalysts in Li-S batteries. [180][181][182][183][184][185][186]…”

Hafnium Diboride Spherical Superstructure Born of 5d‐Metal Hf‐MOF‐Induced p Orbital Activity of B Atom and Enhanced Kinetics of Sulfur Cathode Reaction

“…[ 14 ] The high‐efficiency catalysts that could accelerate the catalytic conversion of polysulfides are considered to be an “active way” to effectively accommodate the shuttle effect. [ 15–17 ]…”

“…[14] The high-efficiency catalysts that could accelerate the catalytic conversion of polysulfides are considered to be an "active way" to effectively accommodate the shuttle effect. [15][16][17] The improvement in the intrinsic catalytic activity of "suitable catalysts" has become the gold standard for improving the troublesome problem of sulfur cathodes. Zhang et al modified the activity of tin dioxide nanocatalysts by crystal plane engineering, revealing that the SnO 2 (332) crystal plane is rich in unsaturated coordination Sn sites, thereby increasing the conversion rate of polysulfides.…”