A Conductive Ni₂P Nanoporous Composite with a 3D Structure Derived from a Metal–Organic Framework for Lithium–Sulfur Batteries

Abstract

Sulfur cathodes have attracted significant attention as next-generation electrode material candidates due to their considerable theoretical energy density. The main challenge in developing long-life Li-S batteries is to simultaneously suppress the shuttle effect and high areal mass loading of sulfur required for practical applications. To solve this problem, we have designed a novel nickel phosphide nanoporous composite derived from metal-organic frameworks (MOFs) as sulfur host materials. Homogeneous distribution of Ni P nanoparticles significantly avoids soluble polysulfides migrating out of the framework through strong chemical interactions, and the conductive 3D skeleton offers an accelerating electron transport. As a result, S@Ni P/NC has exhibited an enhanced performance of 1357 mAh g initially at 0.2 C (1 C=1675 mA g ) and remaining at 946 mAh g after 300 cycles. Even at an areal mass loading of sulfur as high as 4.6 mg cm , the electrode still showed an excellent specific capacity of 918 mAh g .

Multifunctional Electrocatalytic Cathodes Derived from Metal–Organic Frameworks for Advanced Lithium‐Sulfur Batteries

“…This decrease in overpotential betweenthe two cathodes indicates ac atalytic effect by decreasing the reaction barrier, which is clearly causedb yt he preferential chemical adsorption of polysulfides in the CoP matrix. [42,56] The measured parameters of peak voltages and peak currentd ensitiesa re given in Ta bles S3 and S4, respectively. Next,t he S@CoP-N-GC cell was evaluated by galvanostatic charge/discharge tests at variousc urrent rates of 0.1 Ct o2C in the voltage range 1.7-2.8 V. As shown in Figure 5b,t he S@CoP-N-GC cell exhibited the typical dischargev oltage plateau, corresponding to the formation of long-and short-chain LPS, respectively.F igure 5c displays the rate capabilities of S@CoP-N-GC and S@Co-N-GC, respectively.A tt he rate of 0.1 C, S@CoP-N-GC delivers an extremely high specific discharge capacity of 1410 mA hg À1 ,w hich is around8 4% of the theoretical capacity of sulfur,a nd ar eversible chargec apacity of 1414 mA hg À1 ,w ith ac oulombic efficiency of 99.7 %( the 1C rate is defined as the current density of 1675 mA g À1 ).…”

Carbon-based derivatives from metal-organic frameworks as cathode hosts for Li–S batteries

“…Very recently, Cheng et al designed a novel nickel phosphide nanoporous composite derived from MOF-74(Ni) as sulfur host material [166] . Fig.…”

“…(g) SEM image and (h) TEM image of Ni 2 P/NC, inset of (h): statistical pore-size distribution. (i) Cycling performance of S@Ni 2 P/NC over 300 cycles at a rate of 0.2 C. (j) Cycling performance of S@Ni 2 P/NC over 300 cycles at a rate of 0.2 C under high sulfur loading of 4.6 mg cm −2[166] .…”

Revealing the Origin of Highly Efficient Polysulfide Anchoring and Transformation on Anion‐Substituted Vanadium Nitride Host

“…Since 2016, some quasi‐metallic compounds, such as transition metal nitrides (TiN, [ 5 ] VN, [ 6 ] MoN, [ 7 ] Co 4 N, [ 8 ] NbN, [ 9 ] and so forth [ 10 ] ), phosphides (CoP, [ 11 ] Ni 2 P, [ 12 ] MoP, [ 13 ] and FeP [ 14 ] ), and carbides [ 15 ] (MoC [ 16 ] and Mo 2 C [ 17 ] ) were expected to facilitate the diffusion, absorption, and conversion of LiPSs by right of high electrical conductivity, strong polar bonds (LiX, XN, P, and so forth; MS, MCo, Mn, Ti, and so forth) and catalytic activity. [ 18 ] Among these materials, metal nitrides were largely employed as the sulfur host owing to the facile synthesis process by high‐temperature nitridation of metal oxide, hydroxide, or salt precursors in ammonia gas flow.…”