A lithium-oxygen battery would deliver the highest energy density of a rechargeable battery, but the multiphase electrochemical reaction on the air cathode has difficulty proceeding when operated with only solid catalysts. We report here the organic-electrolyte-dissolved iron phthalocyanine (FePc) as a shuttle of (O2)(-) species and electrons between the surface of the electronic conductor and the insulator Li2O2 product of discharge. The Li2O2 is observed to grow and decompose without direct contact with carbon, which greatly enhances the electrochemical performance. Our results signal that the use of molecular shuttles that are catalytically active may prove to be enablers of a practical lithium-air rechargeable battery.

In lithium‐sulfur batteries, small S2–4 molecules show very different electrochemical responses from the traditional S8 material. Their exact lithiation/delitiation mechanism is not clear and how to select proper electrolytes for the S2–4 cathodes is also ambiguous. Here, S2–4 and S8/S2–4 composites with highly ordered microporous carbon as a confining matrix are fabricated and the electrode mechanism of the S2–4 cathode is investigated by comparing the electrochemical performances of the S2–4 and S2–4/S8 electrodes in various electrolytes combined with theoretical calculation. Experimental results show that the electrolyte and microstructure of carbon matrix play important roles in the electrochemical performance. If the micropores of carbon are small enough to prevent the penetration of the solvent molecules, the lithiation/delithiation for S2–4 occurs as a solid‐solid process. The irreversible chemically reactions between the polysulfudes and carbonates, and the dissolution of the polysulfides into the ethers can be effectively avoided due to the steric hindrance. The confined S2–4 show high adaptability to the electrolytes. The sulfur cathode based on this strategy exhibits excellent rate capability and cycling stability.

Energy storage on paper: paper-based, all-solid-state, and flexible supercapacitors were fabricated, which can be charged by a piezoelectric generator or solar cells and then discharged to power a strain sensor or a blue-light-emitting diode, demonstrating its efficient energy management in self-powered nanosystems.

The insulating phase transition in a VO2 nanobeam when subjected to external‐strain is utilized to fabricate a quick response time, highly reproducible, and high gauge factor strain sensor. Raman spectroscopy combined with electromechanical measurement reveals the working principle.

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