The construction of multi‐heteroatom‐doped metal‐free carbon with a reversibly oxygen‐involving electrocatalytic performance is highly desirable for rechargeable metal‐air batteries. However, the conventional approach for doping heteroatoms into the carbon matrix remains a huge challenge owing to multistep postdoping procedures. Here, a self‐templated carbonization strategy to prepare a nitrogen, phosphorus, and fluorine tri‐doped carbon nanosphere (NPF‐CNS) is developed, during which a heteroatom‐enriched covalent triazine polymer serves as a “self‐doping” precursor with C, N, P, and F elements simultaneously, avoiding the tedious and inefficient postdoping procedures. Introducing F enhances the electronic structure and surface wettability of the as‐obtained catalyst, beneficial to improve the electrocatalytic performance. The optimized NPF‐CNS catalyst exhibits a superb electrocatalytic oxygen reduction reaction (ORR) activity, long‐term durability in pH‐universal conditions as well as outstanding oxygen evolution reaction (OER) performance in an alkaline electrolyte. These superior ORR/OER bifunctional electrocatalytic activities are attributed to the predesigned heteroatom catalytic active sites and high specific surface areas of NPF‐CNS. As a demonstration, a zinc‐air battery using the NPF‐CNS cathode displays a high peak power density of 144 mW cm−2 and great stability during 385 discharging/charging cycles, surpassing that of the commercial Pt/C catalyst.

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A tunable and practical synthesis of electrophilic sulfenylating reagents, thiosulfonates and disulfides, from inexpensive and easily available sulfonyl chlorides, has been developed. By appropriate choice of solvents, the reaction of sulfonyl chlorides and tetrabutylammonium iodide gave the target products in good to excellent yields, respectively. These transformations probably proceed through a reducing–coupling pathway.magnified image

To meet various practical requirements and enhance human experience, hydrogels possessing multifunctionality are of great significance for flexible wearable sensors. Herein, a novel strategy has been developed to fabricate nanocomposite hydrogels with a combination of excellent stretchability, rapid recoverability, self-healing, and outstanding adhesiveness. The PAAc/SiO2-g-PAAm nanocomposite hydrogels were facilely prepared through the polymerization of acrylic acid (AAc) using SiO2-g-polyacrylamide core–shell hybrid nanoparticles (SiO2-g-PAAm) as the dynamic cross-linking center. The densely dynamic hydrogen bonds between PAAc matrices and grafted PAAm chains could reversibly be destructed and reconstructed to dissipate a large amount of energy. Due to this unique feature, the formulated hydrogels showed a wide spectrum of desirable properties, including skin-mimetic modulus, excellent stretchability (1600%), exceptional self-healing properties (96.5% at ambient temperature), and fast recoverability. The sensors fabricated with the prepared hydrogels exhibited a high detection sensitivity in the strain range from 50% to 500% with a gauge factor value of 5.86, rapid response time, and good antifatigue performance. Depending on the outstanding adhesiveness, this sensor could attach to different substrates to release the real-time motion monitoring. In the practical wearable sensing test, various human motions, including tiny-scaled swallowing, laughing, and speaking, as well as large-scaled wrist, elbow, and knee movements during basketball shooting, could be sensed. These demonstrations heralded the potential application of our sensor in accurate and long-term human motion monitoring.

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Multifunctional carbon nanofibers (CNFs, see picture), fabricated by a simple electrospinning method, show not only outstanding conductive and magnetic but also superhydrophobic characteristics, which make these materials attractive for the application as corrosive protection and electromagnetic shielding coating. The conductive and magnetic properties of these materials are maintained by the superhydrophobic surfaces.

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The construction of multiple heteroatom-doped porous carbon with unique nanoarchitectures and abundant heteroatom active sites is promising for reversible oxygeninvolving electrocatalysis. However, most of the synthetic methods required the use of templates to construct precisely designed nanostructured carbon. Herein, we introduced an ultrasound-triggered route for the synthesis of a piperazine-containing covalent triazine framework (P-CTF). The ultrasonic energy triggered both the polycondensation of monomers and the assembly into a nanoflower-shaped morphology without utilizing any templates. Subsequent carbonization of P-CTF led to the formation of nitrogen, phosphorus, and fluorine tri-doped porous carbon (NPF@CNFs) with a well-maintained nanoflower morphology. The resultant NPF@CNFs showed high electrocatalytic activity and stability toward bifunctional electrolysis, which was better than the commercial Pt/C and IrO 2 electrocatalysts toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively. As a further demonstration, employing NPF@CNFs as air electrode materials resulted in an excellent performance of liquid-state and solid-state Znair batteries, showing great potentials of the obtained multiple heteroatom-doped porous carbon electrocatalysts for wearable electronics.