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Rechargeable metal–sulfur batteries encounter severe safety hazards and fast capacity decay, caused by the flammable and shrinkable separator and unwanted polysulfide dissolution under elevated temperatures. Herein, a multifunctional Janus separator is designed by integrating temperature endurable electrospinning polyimide nonwovens with a copper nanowire‐graphene nanosheet functional layer and a rigid lithium lanthanum zirconium oxide‐polyethylene oxide matrix. Such architecture offers multifold advantages: i) intrinsically high dimensional stability and flame‐retardant capability, ii) excellent electrolyte wettability and effective metal dendritic growth inhibition, and iii) powerful physical blockage/chemical anchoring capability for the shuttled polysulfides. As a consequence, the as constructed lithium–sulfur battery using a pure sulfur cathode displays an outstandingly high discharge capacity of 1402.1 mAh g−1 and a record high cycling stability (approximately average 0.24% capacity decay per cycle within 300 cycles) at 80 °C, outperforming the state‐of‐the‐art results in the literature. Promisingly, a high sulfur mass loading of ≈3.0 mg cm−2 and a record low electrolyte/sulfur ratio of 6.0 are achieved. This functional separator also performs well for a high temperature magnesium–sulfur battery. This work demonstrates a new concept for high performance metal–sulfur battery design and promises safe and durable operation of the next generation energy storage systems.

We report a new method for the facile and fast synthesis of poly(NMA-co-VCL) (NMA ¼ N-methylolacrylamide, VCL ¼ N-vinylcaprolactam) hydrogels via infrared laser ignited frontal polymerization (LIFP). Once LIFP was initiated, no further energy was required for the following polymerization. We investigated the dependence of the frontal velocity and temperature of the LIFP on the NMA : VCL weight ratio in detail, as well as the swelling behavior and morphology properties of the as-prepared hydrogels. The swelling capacity of the hydrogels prepared by LIFP was superior to that obtained by the traditional thermal frontal polymerization (TFP) method. More interestingly, LIFP could be successfully carried out using a long range infrared laser inducer with remote control. With a further increase in the infrared laser energy, longer range LIFP could be also achieved, making it possible to deal with spilled toxic substances without being close to the location of the reaction.

Understanding the electrolyte-metal anode interface passivating mechanism is crucial for the buildup of sustainable and low cost alkali (earth) metal batteries. Trace H2O-assisted Mg2+-anion ion pair decomposition on a model...

Mechanochromic materials which control their color variation by straightforward effective mechanical stimuli are useful for applications including switches, display devices, and sensors. It is still challenging to create mechnochromic materials with wide‐range color tunability, fast response, and sensitivity to pressure <10 kPa. Here a facile strategy to fabricate very sensitive and reversibly mechanochromic elastic photonic hydrogels (EPHs) is demonstrated. The hydrogels exhibit reversible full‐color variation within 1 s under each compression–decompression cycle. Importantly, EPH films display versatile touch‐induced chromatic behavior even under forces below 0.5 N or pressures down to 1 kPa. Furthermore, rewritable displays on EPH films are realized by the exertion of forces without any external inks. This work may provide a new way to develop smart skin materials with integrated functions of tactile sensing and color variation, as well as touch‐based flexible displays.