Graphdiyne-like Porous Organic Framework as a Solid-Phase Sulfur Conversion Cathodic Host for Stable Li–S Batteries

Abstract

As a unique branch of Li−S batteries, solid-phase sulfur conversion polymer cathodes have shown superior stability with fast ion-transfer kinetics and high discharge capacities owing to the mere existence of short-chain sulfur species during charging/ discharging. However, representative compounds such as sulfurized polyacrylonitrile (SPAN) and polyaniline (SPANI) suffer from low sulfur contents and poor cycling performances under large current densities due to the sulfurization occurring only on polymers' surface. Here, a graphdiyne-like porous organic framework, denoted as GPOF, is synthesized and used as a host for enabling solid-phase sulfur conversion. Plenty of unsaturated bonds in GPOF provide sufficient reaction sites to bind sulfur chains, resulting in a high active sulfur content in the cathode. Moreover, the microporous GPOF possesses suitable cavities to accommodate the volume expansion, leading to favorable long-term cycling stability. As a result, the sulfurized GPOF cathode (SGPOF-320) displays outstanding electrochemical stability with negligible capacity decline after 250 cycles at 0.2 C with an average discharge capacity of 925 mA h g −1 . Our work applies a facile procedure to produce sulfur conversion porous polymer cathodes, which could provide a proper way for exploring more suitable cathode materials for high-performance Li−S batteries.

Sulfurized Polypropylene as Low‐Cost Cathode Material for High‐Capacity Lithium‐Sulfur Batteries

“…[36] Moreover, the lithium diffusion coefficients (D Li, cathodic = 4.47 × 10 À 9 and D Li, anodic = 1.08 × 10 À 8 cm 2 /s) were obtained using the Randles-Sevcik equation (Equation S1); [37] these are comparable to reported cathodes such as SPAN, SPANI or graphdiyne-like porous organic frameworks (Table S2). [28,38,39] Figure 6c shows a voltage curve for an S/PP-500 cathode material using the GITT technique. The curves display a pair of discharge and charge plateaus, which is in line with the discharge profile and strongly implies a solid phase reaction.…”

“…[18,19] Representative compounds are sulfurized poly(acrylonitrile) (SPAN), [20][21][22][23][24][25] or sulfurized carbyne, [26] alucone-coated CÀ S electrodes [27] and graphdiyne-like porous organic frameworks. [28] Cathode materials in this category provide high specific discharge capacity and stable performance owing to the absence of the polysulfideshuttle. However, one major drawback of these materials is the low sulfur loading.…”

“…However, one major drawback of these materials is the low sulfur loading. SPAN has a sulfur loading lower than 45 wt %, [21][22][23][24][25] while the graphdiyne-like porous organic frameworks have sulfur loadings up to 56.8 wt%, [28] which is the highest for cathode materials with sole solid phase transformation. Herein, we report a sulfur-containing polymeric cathode material with sulfur loadings up to 68 wt% that can be used in polysulfideshuttle free LiÀ S batteries, namely sulfurized polypropylene (S/ PP-500), which is prepared via a facile one-step reaction of S 8 with polypropylene (PP) at 500 °C.…”

Porous organic polymers for drug delivery: hierarchical pore structures, variable morphologies, and biological properties

“…In recent years, porous polymers have received considerable attention and exhibited important applications in gas storage and separation, 1,2 adsorption, 3,4 catalysis, 5,6 energy storage, 7,8 and drug delivery. [9][10][11] Compared to conventional inorganic porous materials (such as zeolites, 12 porous carbons, [13][14][15] and mesoporous silica 16 ) and metal-organic frameworks (MOFs), [17][18][19][20][21][22][23] porous organic polymers (POPs) offer excellent stability, high specific surface areas, and ease of functionalization, making them suitable for advanced applications (Table 1).…”

Turning Electronic Waste to Continuous-Flow Reactor Using Porous Aromatic Frameworks

“…Among the current large number of porous materials, porous aromatic frameworks (PAFs) have received great attention owing to their permanent porosity and functionality. − PAFs are constructed from diverse and easily designed organic building units, which are linked to extended frameworks through various coupling reactions. PAFs have made significant progress in the applications of catalysis, sensing, gas separation and storage, drug delivery, batteries, and separation of organic molecules. − Particularly, PAFs feature high thermal and chemical stability owing to their carbon–carbon linkage. Its high stability in water/acid/alkaline medium makes it a promising candidate for gold extraction from acidic aqua regia leachate of e-waste.…”