The Effects of Cross-Linking in a Supramolecular Binder on Cycle Life in Silicon Microparticle Anodes

Self-healing supramolecular binder was previously found to enhance the cycling stability of micron-sized silicon particles used as the active material in lithium-ion battery anodes. In this study, we systematically control the density of cross-linking junctions in a modified supramolecular polymer binder in order to better understand how viscoelastic materials properties affect cycling stability. We found that binders with relaxation times on the order of 0.1 s gave the best cycling stability with 80% capacity maintained for over 175 cycles using large silicon particles (∼0.9 um). We attributed this to an improved balance between the viscoelastic stress relaxation in the binder and the stiffness needed to maintain mechanical integrity of the electrode. The more cross-linked binder showed markedly worse performance confirming the need for liquid-like flow in order for our self-healing polymer electrode concept to be effective

Nonhalogenated Solvent Processable and Printable High-Performance Polymer Semiconductor Enabled by Isomeric Nonconjugated Flexible Linkers

One major advantage of organic electronics is their superior processability relative to traditional silicon-based materials. However, most high-performing polymer semiconductors exhibit poor solubility and require toxic chlorinated solvents coupled with inefficient coating methods such as spin-coating for device fabrication. Therefore, developing polymer semiconductors that are processable in environmentally benign solvents and compatible with effective printing techniques while maintaining good charge transport properties is crucial for the industrialization of low-cost and lightweight plastic electronics. In this study, alkyl flexible linkers with branched tertiary carbon atoms are inserted to a high-mobility diketopyrrolopyrrole-based polymer backbone to suppress polymer aggregation in solution, decrease crystallinity, and increase free volume. The polymer readily dissolves in industrial solvents and shows a 70-fold increase in solubility compared to its fully conjugated counterpart. Furthermore, due to its high solubility, the polymer can be inkjet-printed and solution-sheared at high concentrations using eco-friendly solvents such as <i>p</i>-xylene and 2-methyltetra­hydrofuran with a maximum hole mobility of 2.76 cm² V^–1 s^–1 and on–off ratio above 10⁵ in organic field-effect transistors

An Aqueous Inorganic Polymer Binder for High Performance Lithium–Sulfur Batteries with Flame-Retardant Properties

Lithium–sulfur (Li–S) batteries are regarded as promising next-generation high energy density storage devices for both portable electronics and electric vehicles due to their high energy density, low cost, and environmental friendliness. However, there remain some issues yet to be fully addressed with the main challenges stemming from the ionically insulating nature of sulfur and the dissolution of polysulfides in electrolyte with subsequent parasitic reactions leading to low sulfur utilization and poor cycle life. The high flammability of sulfur is another serious safety concern which has hindered its further application. Herein, an aqueous inorganic polymer, ammonium polyphosphate (APP), has been developed as a novel multifunctional binder to address the above issues. The strong binding affinity of the main chain of APP with lithium polysulfides blocks diffusion of polysulfide anions and inhibits their shuttling effect. The coupling of APP with Li ion facilitates ion transfer and promotes the kinetics of the cathode reaction. Moreover, APP can serve as a flame retardant, thus significantly reducing the flammability of the sulfur cathode. In addition, the aqueous characteristic of the binder avoids the use of toxic organic solvents, thus significantly improving safety. As a result, a high rate capacity of 520 mAh g^–1 at 4 C and excellent cycling stability of ∼0.038% capacity decay per cycle at 0.5 C for 400 cycles are achieved based on this binder. This work offers a feasible and effective strategy for employing APP as an efficient multifunctional binder toward building next-generation high energy density Li–S batteries

Quadruple H‑Bonding Cross-Linked Supramolecular Polymeric Materials as Substrates for Stretchable, Antitearing, and Self-Healable Thin Film Electrodes

Herein, we report a de novo chemical design of supramolecular polymer materials (SPMs-<b>1</b>–<b>3</b>) by condensation polymerization, consisting of (i) soft polymeric chains (polytetramethylene glycol and tetraethylene glycol) and (ii) strong and reversible quadruple H-bonding cross-linkers (from 0 to 30 mol %). The former contributes to the formation of the soft domain of the SPMs, and the latter furnishes the SPMs with desirable mechanical properties, thereby producing soft, stretchable, yet tough elastomers. The resulting SPM-<b>2</b> was observed to be highly stretchable (up to 17 000% strain), tough (fracture energy ∼30 000 J/m²), and self-healing, which are highly desirable properties and are superior to previously reported elastomers and tough hydrogels. Furthermore, a gold, thin film electrode deposited on this SPM substrate retains its conductivity and combines high stretchability (∼400%), fracture/notch insensitivity, self-healing, and good interfacial adhesion with the gold film. Again, these properties are all highly complementary to commonly used polydimethylsiloxane-based thin film metal electrodes. Last, we proceed to demonstrate the practical utility of our fabricated electrode via both in vivo and in vitro measurements of electromyography signals. This fundamental understanding obtained from the investigation of these SPMs will facilitate the progress of intelligent soft materials and flexible electronics

Quadruple H‑Bonding Cross-Linked Supramolecular Polymeric Materials as Substrates for Stretchable, Antitearing, and Self-Healable Thin Film Electrodes

Herein, we report a de novo chemical design of supramolecular polymer materials (SPMs-<b>1</b>–<b>3</b>) by condensation polymerization, consisting of (i) soft polymeric chains (polytetramethylene glycol and tetraethylene glycol) and (ii) strong and reversible quadruple H-bonding cross-linkers (from 0 to 30 mol %). The former contributes to the formation of the soft domain of the SPMs, and the latter furnishes the SPMs with desirable mechanical properties, thereby producing soft, stretchable, yet tough elastomers. The resulting SPM-<b>2</b> was observed to be highly stretchable (up to 17 000% strain), tough (fracture energy ∼30 000 J/m²), and self-healing, which are highly desirable properties and are superior to previously reported elastomers and tough hydrogels. Furthermore, a gold, thin film electrode deposited on this SPM substrate retains its conductivity and combines high stretchability (∼400%), fracture/notch insensitivity, self-healing, and good interfacial adhesion with the gold film. Again, these properties are all highly complementary to commonly used polydimethylsiloxane-based thin film metal electrodes. Last, we proceed to demonstrate the practical utility of our fabricated electrode via both in vivo and in vitro measurements of electromyography signals. This fundamental understanding obtained from the investigation of these SPMs will facilitate the progress of intelligent soft materials and flexible electronics

Quadruple H‑Bonding Cross-Linked Supramolecular Polymeric Materials as Substrates for Stretchable, Antitearing, and Self-Healable Thin Film Electrodes

Herein, we report a de novo chemical design of supramolecular polymer materials (SPMs-<b>1</b>–<b>3</b>) by condensation polymerization, consisting of (i) soft polymeric chains (polytetramethylene glycol and tetraethylene glycol) and (ii) strong and reversible quadruple H-bonding cross-linkers (from 0 to 30 mol %). The former contributes to the formation of the soft domain of the SPMs, and the latter furnishes the SPMs with desirable mechanical properties, thereby producing soft, stretchable, yet tough elastomers. The resulting SPM-<b>2</b> was observed to be highly stretchable (up to 17 000% strain), tough (fracture energy ∼30 000 J/m²), and self-healing, which are highly desirable properties and are superior to previously reported elastomers and tough hydrogels. Furthermore, a gold, thin film electrode deposited on this SPM substrate retains its conductivity and combines high stretchability (∼400%), fracture/notch insensitivity, self-healing, and good interfacial adhesion with the gold film. Again, these properties are all highly complementary to commonly used polydimethylsiloxane-based thin film metal electrodes. Last, we proceed to demonstrate the practical utility of our fabricated electrode via both in vivo and in vitro measurements of electromyography signals. This fundamental understanding obtained from the investigation of these SPMs will facilitate the progress of intelligent soft materials and flexible electronics

Quadruple H‑Bonding Cross-Linked Supramolecular Polymeric Materials as Substrates for Stretchable, Antitearing, and Self-Healable Thin Film Electrodes

Herein, we report a de novo chemical design of supramolecular polymer materials (SPMs-<b>1</b>–<b>3</b>) by condensation polymerization, consisting of (i) soft polymeric chains (polytetramethylene glycol and tetraethylene glycol) and (ii) strong and reversible quadruple H-bonding cross-linkers (from 0 to 30 mol %). The former contributes to the formation of the soft domain of the SPMs, and the latter furnishes the SPMs with desirable mechanical properties, thereby producing soft, stretchable, yet tough elastomers. The resulting SPM-<b>2</b> was observed to be highly stretchable (up to 17 000% strain), tough (fracture energy ∼30 000 J/m²), and self-healing, which are highly desirable properties and are superior to previously reported elastomers and tough hydrogels. Furthermore, a gold, thin film electrode deposited on this SPM substrate retains its conductivity and combines high stretchability (∼400%), fracture/notch insensitivity, self-healing, and good interfacial adhesion with the gold film. Again, these properties are all highly complementary to commonly used polydimethylsiloxane-based thin film metal electrodes. Last, we proceed to demonstrate the practical utility of our fabricated electrode via both in vivo and in vitro measurements of electromyography signals. This fundamental understanding obtained from the investigation of these SPMs will facilitate the progress of intelligent soft materials and flexible electronics

Quadruple H‑Bonding Cross-Linked Supramolecular Polymeric Materials as Substrates for Stretchable, Antitearing, and Self-Healable Thin Film Electrodes

Herein, we report a de novo chemical design of supramolecular polymer materials (SPMs-<b>1</b>–<b>3</b>) by condensation polymerization, consisting of (i) soft polymeric chains (polytetramethylene glycol and tetraethylene glycol) and (ii) strong and reversible quadruple H-bonding cross-linkers (from 0 to 30 mol %). The former contributes to the formation of the soft domain of the SPMs, and the latter furnishes the SPMs with desirable mechanical properties, thereby producing soft, stretchable, yet tough elastomers. The resulting SPM-<b>2</b> was observed to be highly stretchable (up to 17 000% strain), tough (fracture energy ∼30 000 J/m²), and self-healing, which are highly desirable properties and are superior to previously reported elastomers and tough hydrogels. Furthermore, a gold, thin film electrode deposited on this SPM substrate retains its conductivity and combines high stretchability (∼400%), fracture/notch insensitivity, self-healing, and good interfacial adhesion with the gold film. Again, these properties are all highly complementary to commonly used polydimethylsiloxane-based thin film metal electrodes. Last, we proceed to demonstrate the practical utility of our fabricated electrode via both in vivo and in vitro measurements of electromyography signals. This fundamental understanding obtained from the investigation of these SPMs will facilitate the progress of intelligent soft materials and flexible electronics

Quadruple H‑Bonding Cross-Linked Supramolecular Polymeric Materials as Substrates for Stretchable, Antitearing, and Self-Healable Thin Film Electrodes

Herein, we report a de novo chemical design of supramolecular polymer materials (SPMs-<b>1</b>–<b>3</b>) by condensation polymerization, consisting of (i) soft polymeric chains (polytetramethylene glycol and tetraethylene glycol) and (ii) strong and reversible quadruple H-bonding cross-linkers (from 0 to 30 mol %). The former contributes to the formation of the soft domain of the SPMs, and the latter furnishes the SPMs with desirable mechanical properties, thereby producing soft, stretchable, yet tough elastomers. The resulting SPM-<b>2</b> was observed to be highly stretchable (up to 17 000% strain), tough (fracture energy ∼30 000 J/m²), and self-healing, which are highly desirable properties and are superior to previously reported elastomers and tough hydrogels. Furthermore, a gold, thin film electrode deposited on this SPM substrate retains its conductivity and combines high stretchability (∼400%), fracture/notch insensitivity, self-healing, and good interfacial adhesion with the gold film. Again, these properties are all highly complementary to commonly used polydimethylsiloxane-based thin film metal electrodes. Last, we proceed to demonstrate the practical utility of our fabricated electrode via both in vivo and in vitro measurements of electromyography signals. This fundamental understanding obtained from the investigation of these SPMs will facilitate the progress of intelligent soft materials and flexible electronics

Quadruple H‑Bonding Cross-Linked Supramolecular Polymeric Materials as Substrates for Stretchable, Antitearing, and Self-Healable Thin Film Electrodes

Herein, we report a de novo chemical design of supramolecular polymer materials (SPMs-<b>1</b>–<b>3</b>) by condensation polymerization, consisting of (i) soft polymeric chains (polytetramethylene glycol and tetraethylene glycol) and (ii) strong and reversible quadruple H-bonding cross-linkers (from 0 to 30 mol %). The former contributes to the formation of the soft domain of the SPMs, and the latter furnishes the SPMs with desirable mechanical properties, thereby producing soft, stretchable, yet tough elastomers. The resulting SPM-<b>2</b> was observed to be highly stretchable (up to 17 000% strain), tough (fracture energy ∼30 000 J/m²), and self-healing, which are highly desirable properties and are superior to previously reported elastomers and tough hydrogels. Furthermore, a gold, thin film electrode deposited on this SPM substrate retains its conductivity and combines high stretchability (∼400%), fracture/notch insensitivity, self-healing, and good interfacial adhesion with the gold film. Again, these properties are all highly complementary to commonly used polydimethylsiloxane-based thin film metal electrodes. Last, we proceed to demonstrate the practical utility of our fabricated electrode via both in vivo and in vitro measurements of electromyography signals. This fundamental understanding obtained from the investigation of these SPMs will facilitate the progress of intelligent soft materials and flexible electronics